Mathematics Corner :)

[Ameeratul Layl]

:sl:

This is like any other educational corner.
Only, this one will contain lots and lots of numbers:) compared to the rest:)

Well, my dear brothers and sisters, do TRY to help each other as we are ordained to do so.:)
I also hope that those who do not enjoy mathematics will soon come to love it.Its a very challenging subject but it is indeed great fun!!!!:coolsis: :coolious:


Allah ma3ak

[Sanobar]

salam!
hmmm....what do we exactly do here ?post problems in math?? its a good thread sis...m sure i can improve ...!:):):)
ma'salamah

[Ameeratul Layl]

salam!
hmmm....what do we exactly do here ?post problems in math?? its a good thread sis...m sure i can improve ...!:):):)
ma'salamah

:sl:

Yes sister, you type in questions regarding homeworks, courseworks or assignments.

Allah ma3ik

[Ameeratul Layl]

:sl:

Okay, a simple question for all:

Who likes Algebra?
*puts her hands up....* I do!

If anyone needs any help...im here for algebra....okay!:)

Allah ma3akum
I have finally mastered the laws of Algebra *wat laws...?*lol.

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[Amira-Tul-Haya]

:sl:

i like algebra 2 but i dnt need help wid it, i need help wid differentiatin n intergratin graph equations:confused: can ne1 help me?

[Rabiyal]

Hopefully I can...depends on what grade level we are talking about...

[Amira-Tul-Haya]

Hopefully I can...depends on what grade level we are talking about...

im doin AS level maths n need help in using the differentiated n intergrated equations 2 find different points on a graph n wether a point is a minimum or maximum

[Rabiyal]

I have done that stuff, it's been like over 8 yrs....but I am willing to try...
So post the question...

[Amira-Tul-Haya]

the question is:

find the stationary pionts n state if its a minimum or a maximum point
f(x)=2x squared - 9x squared + 12x -7

how do u no if its a min or max?

[Duhaa]

Wouldn't the equation be -7x squared? (because +2 add -9 is -7)
Sorry, not part of your question but it does make it easier and I was just wondering.

[Duhaa]

You differentiate the equation.
Use the rule 'Times by the power and reduce it by one'
So your equation would be -14x +12
Then differentiate again to give -14
From this you can find if it's max or min.
Sorry but I can't remember which way round it is. When I do find out, will post IA.

[Amira-Tul-Haya]

Wouldn't the equation be -7x squared? (because +2 add -9 is -7)
Sorry, not part of your question but it does make it easier and I was just wondering.

dats how the question is given n examiners live just 2 make life hard 4 ppl.

thanx 4 da help! :smile:

[mohakem]

As salamu alikum

If the second derivative is less than 0, the point is a maximum point.
If the second derivative is more than 0, the point is a minimum point.

If the second derivative is 0, the point is neither a maximum point nor a minimum point.

It's kind of 'oposite' to how you might think it woule be.

Wa alikum salam

[Sanobar]

salam!
well algebra is fine with me ...but i hate trignometry there are just too many formulae.....i swear i can do anything in math but not trignometry ! and guess wat my paper has all trig init...it carries all the marks...:(:(

ill ask my doubts later...! :):)
ma'salamah

[Amira-Tul-Haya]

[If the second derivative is less than 0, the point is a maximum point.
If the second derivative is more than 0, the point is a minimum point.

If the second derivative is 0, the point is neither a maximum point nor a minimum point.

It's kind of 'oposite' to how you might think it woule be.

:sl:
thanx 4 da help, i alwayz get confused wid dis, mayb i'll remembr it now or just fail da test i hv on friday if i dnt.

:w:

[mariamq]

Salam, I have 3 questions the first is an algebra one.. Im so lost at the moment and i cannot figure this out.. Im sure its easy for many but i just cannot get it.

1. Use the formula A equals half bh to find A if b equals 9 and h equals 6.

this one is not algebra.

1. what is the length of a diagonal square of side 6 m? Give answer to one decimal place. (also how do i show the working to this answer?

2. A flagpole is held steady by a wire connected to the pole 8 m above ground. The wire is also attached to the ground 3 m from the base of the pole. Find the length of the wire correct to 2 decimal places.

I realllyyyyy neeed to know this, I have no idea about it.

Jazakallah khair.

Wa salam.

[niqaabii]

good news for u all!!!
my husband is a maths teacher..so if anyone needs help ..then just let me kno.and ill get the answers for ya:)

[mohakem]

As salamu alikum

Salam, I have 3 questions the first is an algebra one.. I'm so lost at the moment and i cannot figure this out.. I'm sure it's easy for many but i just cannot get it.

1. Use the formula A equals half bh to find A if b equals 9 and h equals 6.

this one is not algebra.

A = bh / 2 (divided by 2) .

Like it says; A equals half of bh.

It's then simply a matter of substituting b = 9 and h = 6 into the equation,

A = (9 * 6) / 2

which gives us; A = 54 / 2 .This means A = 27

2. what is the length of a diagonal square of side 6 m? Give answer to one decimal place. (also how do i show the working to this answer?

Do you mean, "What is the length of the diagonal of a square of side 6m" ?
If so, this requires Pythagoras theorm. (a^2 (a squared) + b^2 = c^2)

Basically you split the square along the diagonal, leaving two triangles.Take one of the triangles, and you will notice that 2 sides are 6m in length.The other side, the hypotenuse (the diagonal) you must find.

From the formula above give the sides you know the length of as 'a' and 'b' . The hypotenuse (the longest side - the diagonal) is 'c'.

So, c = the square root of a^2 + b^2 . Therefore, c = squareroot of 6^2 + 6^2

Plug the numbers into your calculator and then round of your answer to 1 d.p.

3. A flagpole is held steady by a wire connected to the pole 8 m above ground. The wire is also attached to the ground 3 m from the base of the pole. Find the length of the wire correct to 2 decimal places.

Again, Pythagoras theroem needs to be used here. The wire will be the hypotenuse (c) and the flagpole (8m) will be 'a', and the distance between pole and wire (3) will be 'b'.

c (length of wire) = squareroot of a^2 + b^2 . Therefore c = squareroot of 64 + 9

Its difficult to explain pythagoras theorm without diagrams of the triangles.You might want to take a look at http://www.bbc.co.uk/schools/gcsebit...oremrev2.shtml

Wa alikum salam

[mariamq]

Jazakallah khair. May Allah reward you with a castle in jannah Ameen.. You have beed a great help Mashallah. Well i have more maths to do so inshallah if i dont understand i can just come here.. Once again Jazakallah khair.

[mariamq]

Salam,
I have another one.

A girl 1.5cm tall casts a shadow 2.0m long. At the same time of the day, a man 1.8 m tall casts a shadow x cm long. what is the length of the mans shadow and
and how can we simplify the ratio 1.5 over 2.0 to one with whole numbers?

[mariamq]

OOppss yep its 1.5m

[time_spender]

the answer is simply (1.8/1.5)*(2)
i think that will help!
the scale is (1.5/2) so by doing the: yourheigth/(scale)=answer:)
let me ask my question!
how can you calculate fast the derivative of a 100 multipled factors.something like this:

[(2x+1)(4x^2+7)(54x^4)(5x^3)....(9x+3)]'=?
is there any simple way to do it!
hope i have i said my will right!!
:confused:

[mohakem]

:sl:

the answer is simply (1.8/1.5)*(2)
i think that will help!
the scale is (1.5/2) so by doing the: yourheigth/(scale)=answer:)
let me ask my question!
how can you calculate fast the derivative of a 100 multipled factors.something like this:

[(2x+1)(4x^2+7)(54x^4)(5x^3)....(9x+3)]'=?
is there any simple way to do it!
hope i have i said my will right!!
:confused:

:confused: Could you copy it [the question] from the textbook (if you have it) please.

:w:

[Duhaa]

First you multiply out the first bracket:
(2x + 1)(4x^2 + 7) which if I'm right gives:
(8x^3 + 14x + 4x^2 + 7) which you then mutiply by the next bracket which in your question is (54x^4) which gives:
(432x^7 + 756x^5 + 216x^6 + 378x^4) which you multiply by the next bracket (5x^3) giving:
(2160x^10 + 3780x^8 + 1080X^9 + 1890x^7)
And now multiply all of this to the final bracket (9x + 3):
(19440x^11 + 34020x^9 + 9720x^10 + 17010x^8 + 6480x^10 + 11340x^8 + 3240x^9 + 5670x^7)
Now lastly collect all like terms:
= 19440x^11 + 16200x^10 + 37260x^9 + 28350x^8 + 5670x^7
......and there you have it. The final answer. Phew that took patience. I sometimes wonder about the people who write these questions. They've probably never been kids!
( I hope its right otherwise I think I'll quit doing math.) :)

[time_spender]

Aww thank you Savdah
Probably you have spent time for it!
But I meant the derivation of the whole braket
Sorry….there is no textbook to paste it from there.
(My english is not good..thats why i fear to understand myself to you!)
Let me write it again, I mean( y’)

-----d/dx of ([(2x+1)(4x^2+7)(54x^4)(5x^3)....(9x+3)]) not the result of the bracket

I found something interesting for it
It goes like this:

Y=([(2x+1)(4x^2+7)(54x^4)(5x^3)....(9x+3)])
Now you use the natural logarithm
Lny=ln([(2x+1)(4x^2+7)(54x^4)(5x^3)....(9x+3)]) so it will be more simple:

Lny=ln(2x+1)+ln(4x^2+7)+ln(54x^4)+ln(5x^3)…+ln(9 x+3)

Now you can get the derivation easily:

d/dx====> y’/y=(2/2x+1)+(8x/4x^2+7)+(216x^3/54x^4)+(15x^2/5x^3)+….(9/9x+3)

now y’ obviously equals to:

y’ = y*[(2/2x+1)+(8x/4x^2+7)+(216x^3/54x^4)+(15x^2/5x^3)+….(9/9x+3)]
which y=([(2x+1)(4x^2+7)(54x^4)(5x^3)....(9x+3)]) (our first whole bracket)

that’s the best way I have found….any other solutions?

I sometimes wonder about the people who write these questions. They've probably never been kids!

Haha…they have been kids for a long time sister…once they played with + and -!!!
Let me tell you something....i,m in the 3rd term of civil engineering and I read this solution one year ago.
I just wanted to know that if there is a better solution I use it…that’s all!
wasalam:)

[mariamq]

Jazakallah khair for your reply to m question b4 time spender...

[islamonline]

heheh maths :D:D:D my flavourite :p

[scarlet]

:sl:

I really like algebra but some of the parts i really dont get it:confused:

thats a really good thread sister :sister:, if i need any help in algebra then i'll ask you:)
:peace:

:w:

[The Ruler]

:sl:
right here is wat i did 4 the first question n i dunno how to so som of de other questions. i hope som1 will elp me understand...

x2 = x squared

x-2/ x2-4

i did it as...

x-2/(x+2)(x-2) = 1/(x+2).

is it rite?

now the nxt 1 i need help...

remember x2 = x squared.

x2-49/2x+5 (division sign) 4x-28/4 x2-25

plz help...som1 *pleading*

[thc]

i think that the first question is rite!

[The Ruler]

ok dat 1 mi8 be rite, but how bout the 2nd 1? :? :?
dats da 1 i need help on. :rollseyes

[Muhammad]

:sl:

I didn't quite understand the questions you provided. You gave the equations yet what are we supposed to be finding?

:w:

P.S Threads merged.

[The Ruler]

:sl:

I didn't quite understand the questions you provided. You gave the equations yet what are we supposed to be finding?

:w:

P.S Threads merged.

oops sowweee its simplification. it struck me yeaterdy wen i went to bed at nite dat i didnt day wat u r s'pposd to b findin sowwee bout dat :statisfie

[The Ruler]

yep the question's rite. now sho me da work out :)

[aZn_pLayGurL]

i Like linear equations in maths :p they soo easy even A Level lineas ;P

[The Ruler]

i Like linear equations in maths :p they soo easy even A Level lineas ;P

yeah yeah :rollseyes now som 1s gotta elp me wid dis or i get a detention on monday. its a home work ya no. i gotta get it done other wise

:hiding:

[aZn_pLayGurL]

LoL r ju in college or still in school :p

[The Ruler]

LoL r ju in college or still in school :p

still in skool...yr 10 not yet GCSEs but very sooooon :( :(

SOM1 HELP MEEEEEEEE!!!!!!

[aZn_pLayGurL]

awww al help ju lol bin there dun dat watz da question then?

[Umm_Maysa]

yep the question's rite. now sho me da work out :)

:sl:

check this
http://pg.photos.yahoo.com/ph/imane5...nm=a60cscd.jpg

[The Ruler]

i dunno wat ^^^^dats sposd to b :? :?

[The Ruler]

will do this tomorrow, insha allah.

i v done it now...:happy:

didnt use ma brain b4 ;D ;D

andi got the same answer u mentioned b4 :)

tnx anyway...

[The Ruler]

dunno if im rite, i jus got da same answer as urs dats all :rollseyes

[Umm_Maysa]

i dunno wat ^^^^dats sposd to b :? :?

:sl:
that's showing the workout of the question. just click the link..
Wassalam.

[Umm_Maysa]

u hv PERSONAL rights to tht file, n so no other person can access it :)

:sl:
Oh jazakallahu khairan for point that out. I don't know that. Well seem that Sis Ruler already got the answer so no worries. Anyway feel free to ask...

[The Ruler]

no wonda...i signed in but it didnt work :rollseyes

[Ameeratul Layl]

Salam,

Who will be studying AS/A2 Maths and would like to study here?

Wasalam

[seeker_of_ilm]

:sl:

I did AS last year...gonna be doing A2 next year Insha'allah. Maths is not a bad subject.

[...]

i'm continuing to do A2 maths next year inshaallah:)

[Ameeratul Layl]

:sl:

I did AS last year...gonna be doing A2 next year Insha'allah. Maths is not a bad subject.

:sl:
I find algebra fun. But, I haven't had a lesson with my teacher today. So, I haven't been anything new. I am actually taking maths privately.
Basically, I will need it to study Physics at University. I am in 2nd year A levels for my other subjects. The aim is to get through Maths AS and A2 so I can take them the same time as my other A levels. InshAllah.

So, do you or anyone else know of any good websites to get me to keep my brain going during the holidays?

:w:

[seeker_of_ilm]

:sl:

Erm...What Exam board are you doing...because if its Edexcel...I can give you a site with Past Papers and model solutions.

[Ameeratul Layl]

:sl:

Erm...What Exam board are you doing...because if its Edexcel...I can give you a site with Past Papers and model solutions.

:sl:
My private tutor has not told me what borad-yet. I believe she would have today, but something came up.
Could you kindly send the Edexcel link?
:w:

[seeker_of_ilm]

:sl:

http://www.examsolutions.co.uk/index.php

[Ameeratul Layl]

:sl:

http://www.examsolutions.co.uk/index.php

:sl:
JazakAllah akhee.:)
:w:

[Ameeratul Layl]

:sl:


Given that 256=4 (to the) k
Write down the value of k

I did:

k = 256
----
4

k = 64

But, the answer is wrong. It is meant to be: 4.


Can someone help please?

wasalam

[seeker_of_ilm]

:sl:


Given that 256=4 (to the) k
Write down the value of k

I did:

k = 256
----
4

k = 64

But, the answer is wrong. It is meant to be: 4.


Can someone help please?

wasalam

:sl:

This is how I would do it:

256 = 4 (to the K)

I'd first take log of both sides to make

Log 256 = Log 4 (to the K)

The K can be moved (due to Log laws) before the log to make:

Log 256 = K Log 4

Move the Log 4 to the other side to get:

Log 256/Log 4 = K ( / = divided by)

This should give you the answer 4 :)

Just remember its not 256/4....its LOG 256/LOG 4 (this is a common mistake)

[Malaikah]

:sl:

^yeh those are both right

[Ameeratul Layl]

:sl:
I don't know if this is correct method or not, don't remember:

256 = 4^k
log256 = k log4
log256/log4 = k
k = 4

I think gives correct answer... check on a calculator...

:w:

Salam,
Yes, alhamdullilah it has given the right answer.
I didn't know you had to use log in this.

[Ameeratul Layl]

:sl:

This is how I would do it:

256 = 4 (to the K)

I'd first take log of both sides to make

Log 256 = Log 4 (to the K)

The K can be moved (due to Log laws) before the log to make:

Log 256 = K Log 4

Move the Log 4 to the other side to get:

Log 256/Log 4 = K ( / = divided by)

This should give you the answer 4 :)

Just remember its not 256/4....its LOG 256/LOG 4 (this is a common mistake)

:w:
I can understand why people don't like A level mathematics.
Hmm..I doubt I'll be giving up though.

JazakAllah for your help-everyone!

wasalam

[seeker_of_ilm]

:w:
I can understand why people don't like A level mathematics.
Hmm..I doubt I'll be giving up though.

JazakAllah for your help-everyone!

wasalam

:sl:

Maths is easy though! Makes so much sense....all it takes it practice. Once you learn the methods you'll be laughing

[Ameeratul Layl]

:sl:

Okay, using seekre of ilm's method, I have tried to get the answer for a similar question:



81 = 3 (to the K)

Log 81 = Log 3 (to the K)

Log 81 = K Log 3

Log 81/Log 3 = K

k = 4

Have you all got the same or is it totally wrong?

Wasalam

[seeker_of_ilm]

:sl:

Okay, using seekre of ilm's method, I have tried to get the answer for a similar question:



81 = 3 (to the K)

Log 81 = Log 3 (to the K)

Log 81 = K Log 3

Log 81/Log 3 = K

k = 4

Have you all got the same or is it totally wrong?

Wasalam

:sl:

That answer is correct

[Ameeratul Layl]

:sl:

That answer is correct

:sl:
Oh subhanAllah, maybe I can laugh now.

JazakAllah so much brother.

wasalam

[Ameeratul Layl]

Salam,

Anyone any good at factorising? I mean, the GCSE level. I need to start from scratch.
JazakAllah.
wasalam

[seeker_of_ilm]

Salam,

Anyone any good at factorising? I mean, the GCSE level. I need to start from scratch.
JazakAllah.
wasalam

:sl:

Factorising is easy once you get used to it

[lolwatever]

nemore math questions :?

[Amira-Tul-Haya]

:sl:

does any1 on this forum do pure + mechanics at A2 level?

i really need help with Circular motion which is part of mech, i dont understand it at all so any help at all is welcome..

:w:

[lolwatever]

:sl:

does any1 on this forum do pure + mechanics at A2 level?

i really need help with Circular motion which is part of mech, i dont understand it at all so any help at all is welcome..

:w:

salams,

could you plug any sample problems that u got issues with? its always best explaining things with an actual problem in mind.

all the best
tc salams

[Amira-Tul-Haya]

:sl:

could you plug any sample problems that u got issues with? its always best explaining things with an actual problem in mind.


one question on da topic is:

the orbit of the moon around the earth may be modelled as circular. The time taken 4 the moon 2 make 1 complete orbit is approx 27.32 days.

a) Show that the angular speed of the moon is approx 2.66 X 10tothepower6 radians per sec

b) Assuming that the radius of the circular orbit is approx 3.844 X 10tothepower8 metres, find the speed of the moon, relative 2 the earth, in metres per sec

its an exam type question and i dont understand how 2 work it out, do u think u can help?

:w:

[allah-akbar]

:sl:

could you plug any sample problems that u got issues with? its always best explaining things with an actual problem in mind.


one question on da topic is:

the orbit of the moon around the earth may be modelled as circular. The time taken 4 the moon 2 make 1 complete orbit is approx 27.32 days.

a) Show that the angular speed of the moon is approx 2.66 X 10tothepower6 radians per sec

b) Assuming that the radius of the circular orbit is approx 3.844 X 10tothepower8 metres, find the speed of the moon, relative 2 the earth, in metres per sec

its an exam type question and i dont understand how 2 work it out, do u think u can help?

:w:

:sl:

I think i can help you out with this math problem but i would have to think it through at home today... I will start on it as soon as i get home...

NOTE: guys don't let this topic die.. post some problems :)

:w:

[lolwatever]

:sl:

could you plug any sample problems that u got issues with? its always best explaining things with an actual problem in mind.


one question on da topic is:

the orbit of the moon around the earth may be modelled as circular. The time taken 4 the moon 2 make 1 complete orbit is approx 27.32 days.

a) Show that the angular speed of the moon is approx 2.66 X 10tothepower6 radians per sec

b) Assuming that the radius of the circular orbit is approx 3.844 X 10tothepower8 metres, find the speed of the moon, relative 2 the earth, in metres per sec

its an exam type question and i dont understand how 2 work it out, do u think u can help?

:w:

ok sis isA i'll get bak 2 u on this by end of the day when i get bak :thumbs_up

:w:

[Ameeratul Layl]

peace!

Just a reminder to all, that this thread is still around to post your queries :D

br lolwateva, still waiting for that reply. :D

[Uthman]

[Al-Zaara]

I'm still struggling with Maths.. In a perfect world, either Maths didn't exist or I had more talent in that subject. :exhausted The latter is almost an impossiblity. :-[ *sigh*

Where, oh where did those mathematical genes get lost, that both of my parents so strongly possess? Oh yes! To both of my younger sisters. :rollseyes



I will come to this thread as soon as school starts again, inshaAllah!

[Uthman]

Mashaa'Allah I didn't know you went to school. Sister, you come across as somebody who is much older and intelligent!

[Al-Zaara]

Oh, jazakAllah kheyr for that! Same applies to you, mashaAllah. But I am not sure if you do go to school aswell.. Do you?

I'll be 18 in August. There's plenty of school left for me. :D

[Uthman]

Oh, jazakAllah kheyr for that! Same applies to you, mashaAllah. But I am not sure if you do go to school aswell.. Do you?

I'll be 18 in August. There's plenty of school left for me. :D

JazakAllah Khayr. I'll be 18 next April but I'm in college. When you say school...do you mean college? Because I'm pretty sure 17 year olds go to college!

[Al-Zaara]

JazakAllah Khayr. I'll be 18 next April but I'm in college. When you say school...do you mean college? Because I'm pretty sure 17 year olds go to college!

We iyyak.

English is my 5th language and I use it only online so I don't bother much, I just say school... But correctly said I believe it is to say that I visit an upper secondary school.

You're younger than me. :skeleton:

[Whatsthepoint]

We iyyak.

English is my 5th language and I use it only online so I don't bother much, I just say school... But correctly said I believe it is to say that I visit an upper secondary school.

You're younger than me. :skeleton:

5th?!?
No wonder Finland is such a sucessful country.

[Uthman]

5th?!?
No wonder Finland is such a sucessful country.

Ditto that! 5th language?!

The attitude that many of us Brits take is very much 'Everyone else learns English so why should we bother learning other languages?'.

But not me! :D My parents are from Mauritius so I know Creole which is their language (very similar to French). I got a GCSE in German and French and I'm also doing an A-level in French but I can barely hold a conversation in either of these languages, let alone speak them fluently on an online forum. Argh...so frustrating.

Anyway...

(though I'm the one who started all this)

[Yanal]

What is x -y if x is h? :D

[Woodrow]

What is x -y if x is h? :D

h-y

[Abdu-l-Majeed]

Hey. ;D

[Yanal]

Ahh Grandpa Woody, it was a joke , I think.

[chacha_jalebi]

2y x 5y = ?

go on yanal :D

[Yanal]

Well the answer is ....10yy.
Next question: What is c+h+a+c+h+a=

[Whatsthepoint]

Well the answer is ....10yy.
Next question: What is c+h+a+c+h+a=

2(a+c+h+e) - 2e

[Güven]

got some real math questions ? :hmm:

[Whatsthepoint]

got some real math questions ? :hmm:

Here you go nature boy:


Find all prime numbers p if:
p + 28 = prime
p + 56 = prime

[Whatsthepoint]

Here you go nature boy:


Find all prime numbers p if:
p + 28 = prime
p + 56 = prime

Nobody?

[Cabdullahi]

the question seems unclear,do we have to find out what p is? but then you say find all prime numbers that would fit in the equation

well the first one

19 + 28 = 47 which is a prime number ? is that how it is im not sure

the second equation
11 + 56 = 67 which is a prime number

[Cabdullahi]

ohhh i think you want us to find all the possibilities?? is that correct brother wtp?

[Güven]

Ive never seen such a question before , im sorry :exhausted

[Whatsthepoint]

ohhh i think you want us to find all the possibilities?? is that correct brother wtp?

You have to find every prime number that fits both equations.
19 + 28 = 47
however
19 + 56 is 75 which is not prime.
so p is not 19.

And you mustn't solve it by trying.

[Cabdullahi]

3 + 28 = 31

3 + 56 = 59

[Cabdullahi]

61 + 28 = 89

61 + 56 = 117


???

[Whatsthepoint]

61 + 28 = 89

61 + 56 = 117


???

Nope, 117 = 39 × 3

[Whatsthepoint]

3 + 28 = 31

3 + 56 = 59

Yep, but that was a guess.
Try figuring it out in a mathematical way.

[Woodrow]

Yep, but that was a guess.
Try figuring it out in a mathematical way.

I believe the question needs some parameters, otherwise there will be infinite possibilities. No matter what the largest one is, we can never rule out that there is a larger possibility.

[Whatsthepoint]

I believe the question needs some parameters, otherwise there will be infinite possibilities. No matter what the largest one is, we can never rule out that there is a larger possibility.

Nope. 3 is the only solution.

[Woodrow]

Nope. 3 is the only solution.

I must be misinterpreting something or have totally forgot how to find prime numbers (Which is very probable)

Math never was one of my strong points.

[Cabdullahi]

56+28= 84

84 divide by 2(p) = 42

42 - 28 = 14
56 - 42 = 14

28 / 14 = 2
56 / 14 = 4

4 + 2 = 6

6 divide by 2(p) = 3

i think its soooo wrong lol

[Whatsthepoint]

I must be misinterpreting something or have totally forgot how to find prime numbers (Which is very probable)

Math never was one of my strong points.

p is prime
p + 28 is prime
p + 56 is prime
That's all there is to it.

I'll give it some more time.

[Cabdullahi]

inshallah i would ask brother wtp to give us daily equation to help boost our mathmatical knowledge

[Whatsthepoint]

56+28= 84

84 divide by 2(p) = 42

42 - 28 = 14
56 - 42 = 14

28 / 14 = 2
56 / 14 = 4

4 + 2 = 6

6 divide by 2(p) = 3

i think its soooo wrong lol

haha, you're very creative!:DBut basically what you did is this
28 = a
56 = 2a

a + 2a = 3a
3a/2 = 1.5a

1,5a - a = 0,5a
2a -1,5a = 0,5a

2a/0,5a = 4
a/0,5a = 2

4 + 2 = 6
6/2 = 3

so, it works with every a and 2a number.

the solution to this problem is simpler.

[Whatsthepoint]

inshallah i would ask brother wtp to give us daily equation to help boost our mathmatical knowledge

Can do.

[malayloveislam]

Assalamualaikum,

I am bad in maths while I'm in school, but this thread is good although I had left maths for more than three years. Last time I'm learning maths because I have to, now I can learn it for fun : ))))

[Whatsthepoint]

I'll leave the prime thingy to potential solvers.
Here's an easier one, 8 grade math or something:

Ahmed, Mahmud, Muhammad, and Mehmet decided to buy a football. Ahmed contributed 40%, Mahmud payed 3/7 of what the other 3 gave, Muhammad gave 25% of what the other 3 gave and Mehmet payed 10 pounds.
How much did the bunch pay for the ball?

[Abdu-l-Majeed]

p is prime
p + 28 is prime
p + 56 is prime
That's all there is to it.

I'll give it some more time.

Every prime, other then 3, is 3k+1 or 3k-1.

If p=3k-1, then p + 28 = 3k + 27 = 3 (k + 9), this can't be a prime.

If p = 3k+1, then p + 56 = 3 (k+19), also not a prime.

So, the solution are the primes which are divisible by 3. The only solution is number 3. ;D

[Whatsthepoint]

Every prime, other then 3, is 3k+1 or 3k-1.

If p=3k-1, then p + 28 = 3k + 27 = 3 (k + 9), this can't be a prime.

If p = 3k+1, then p + 56 = 3 (k+19), also not a prime.

So, the solution are the primes which are divisible by 3. The only solution is number 3. ;D

Yep.
Are you a math student by chance?

[Yanal]

Bismillahair Ramanhair Raheem
:sl:
Here is a real math question : How do you do area and perimeter? need very detailed version ( perhaps from zak:D). I'm asking because I failed this portion of math and have an upcoming exam about it. Jazakallah kayr.
:w:

[Abdu-l-Majeed]

Yep.
Are you a math student by chance?

Near. :D I'm studying Computer Sciences, so we have tones of math. ;-)

@ Yanal:

:wasalamex

Which figure? Unless you know calculus, you have to tell us which figure. :D

[Whatsthepoint]

Near. :D I'm studying Computer Sciences, so we have tones of math. ;-)

thats good, you study in Sarajevo?

[Abdu-l-Majeed]

Yes, now in Sarajevo. The year before this I was in Podgorica.

[Yanal]

All possible shapes pls.First simple ones such as square, triangle, trapezoid and rectangles first:).

[Whatsthepoint]

All possible shapes pls.First simple ones such as square, triangle, trapezoid and rectangles first:).

http://www.mathleague.com/help/geometry/area.htm

[Yanal]

Simple explaining I can't understand a word:?

[*Yasmin*]

what don't you understand yanal maybe i can help
you must think that math is easy that's first
then open the math's books

[Whatsthepoint]

what don't you understand yanal maybe i can help
you must think that math is easy that's first
then open the math's books

And if that doesn't work?

[*Yasmin*]

close the book and pray :D

[Yanal]

I still need help on Area and perimeter, for exams. We started Algebra and it's a piece of LI:D Guyz those tips are not helping.

[Woodrow]

I still need help on Area and perimeter, for exams. We started Algebra and it's a piece of LI:D Guyz those tips are not helping.

The perimeter is simply the length of the sides added together.
That is easy for polygons for circles and curved shapes you will have to wait until you get to spherical trigonometry.

For area
For regular 4 sided polygons the area is the height multiplied by the height. For triangles it is the 1/2 the altitude times the base and for Circles it is pi times R squared.

For irregular shapes you have to break the shape down into regular shapes figure each one separately and add them together.

[Yanal]

See I get confused with big words in the text book. And the way it's cut up etc.

[*Yasmin*]

can you scan question\s from your book & i'll try to solve it
when u see solved question u will understand better >>my math teacher was saying it.

[Yanal]

Ahh I don't have a question I'm trying to learn before my exams :uuh:

[Woodrow]

Ahh I don't have a question I'm trying to learn before my exams :uuh:

Therein lies the difficulty. You first need to find what type of questions the exam will be testing for and then give an example of ones you don't understand. If you have no trouble understanding your current math book and lessons. You will have no trouble with the exam. If you are having trouble with your current book, give an example of the questions you have problems with.

[Vito]

Bismillahair Ramanhair Raheem
:sl:
Here is a real math question : How do you do area and perimeter? need very detailed version ( perhaps from zak:D). I'm asking because I failed this portion of math and have an upcoming exam about it. Jazakallah kayr.
:w:

http://www.bgfl.org/bgfl/custom/reso...rea/index.html

how about that?

[Yanal]

No currently we are at Algebra which is pretty neutral for me.

[Woodrow]

No currently we are at Algebra which is pretty neutral for me.

Have you reached the level where you are name the various types of equations?

I ask that to get some idea as to what type questions will be on your exam.

[Na7lah]

what grade are u in Yanal if u dnt mind me asking

[Yanal]

Bro woodrow I don't think we are. An example would be -2t+34=54-6t.
Sister I don't mind , I'm in grade 8.

[Vito]

Been years but let me see if I can get this right. I don't think it matters how you start it off you will still get the same answer

-2t+34=54-6t
(I added 6t to both sides which cancels out -6t)

-2+6t+34=54
(-2 + 6t = 4t)

4t+34=54
(I subtracted 34 from both sides to cancel out +34)

4t=20
(I divide 4 into 20 to leave 't' by itself)

t=5?

[Woodrow]

Bro woodrow I don't think we are. An example would be -2t+34=54-6t.
Sister I don't mind , I'm in grade 8.

Adding 6t to both sides I get
6t-2t+34=54-6t+6t
reducing to
4t+34=54
reducing to
4t=20
reducing to
t=5

[Yanal]

Guyz I don't need help on that. I'm just showing which kind of algebra we are doing.

[Na7lah]

Guyz I don't need help on that. I'm just showing which kind of algebra we are doing.

lol i remember that part of math clearly, what do you need help with then? finals are suppose to be coming up for the first term right? my sister has them in one or two weeks i think

[Yanal]

Same:uuh: At January 26.:uuh: my first exams. I need help on area and perimeter, also I can do a bit with geometry too.

[Yanal]

^ Abd I haven't started to study for even one subject :uuh:. Should I start?:uuh:

[Na7lah]

ofcourse, time can be your best friend and your worst enemy, don't think that just cuz u have a lot of time you should put off studying, i'd say get done with studying first then do what ever else u want to

[Na7lah]

Same:uuh: At January 26.:uuh: my first exams. I need help on area and perimeter, also I can do a bit with geometry too.

perimeter: add together all the sides

area:

triangle: 1/2bh, mutiply the base and the hight then multiply that by 1/2

Square: LxL multiply the two sides

The area of a parallelogram is b × h

the area of the trapezoid is
1/2 × h × (a + b) .

The area of a circle is Pi × r2 or Pi × r × r, where r is the length of its radius. Pi is a number that is approximately 3.14159.

i won't blame you if you hate finding the area of a circle lol i use to hate it too :-[

this site it really good http://www.mathleague.com/help/geometry/area.htm just open your mind and you'll see the facts going right in :p

all the best in your tests inshallah :)

[Yanal]

Ugh I'll just check the website out. Jazakallah and hope your sister does well as me.

[Woodrow]

^ Abd I haven't started to study for even one subject :uuh:. Should I start?:uuh:

The reality of life. Procrastination wins again.

GET TO YOUR BOOKS

NOW

[Yanal]

Proscration...what:? What does that mean?

[Na7lah]

laying off your work for later

[Woodrow]

Proscration...what:? What does that mean?

Procrastination means putting off doing things, you need to do.

[Yanal]

I know but I am so dang LAZY can't even pray:( Please someone yell at me.

[Tilmeez]

1. Grab a calculator. (you won't be able to do this one in your head)
2. Key in the first three digits of your phone number (NOT the area code)
3. Multiply by 80
4. Add 1
5. Multiply by 250
6. Add the last 4 digits of your phone number
7. Add the last 4 digits of your phone number again.
8. Subtract 250
9. Divide number by 2

Do You Recognize the Answer?

check this out. do this work for you? if so then how?

[Tilmeez]

how many digits do you have in you mobile number (Excluding your service provider and country codes)?

[Musaafirah]

1. Grab a calculator. (you won't be able to do this one in your head)
2. Key in the first three digits of your phone number (NOT the area code)
3. Multiply by 80
4. Add 1
5. Multiply by 250
6. Add the last 4 digits of your phone number
7. Add the last 4 digits of your phone number again.
8. Subtract 250
9. Divide number by 2

Do You Recognize the Answer?

All I'm saying is....
That's one heck of a long way to get your phone number...

[Yanal]

It does not work for me,neither do I recognize the number. What is it suppose to be recognized by? Your phone number? Birthday?
PS zÂk is your signature accurate and different for every person?

[doorster]

It does not work for me,neither do I recognize the number. What is it suppose to be recognized by? Your phone number? Birthday?

^^ just pick any 7 digit number

[Yanal]

Oh I thought it was related to my phone number.

[Musaafirah]

Our phone numbers here are seven digits, hence the reason for it being related to the phone number.
As Doorster said, any 7 digit number will do. Just write down what the numbers were to begin with.
I seriously can't get over the fact that I actually followed the instructions :muddlehea

[Woodrow]

PS zÂk is your signature accurate and different for every person?

I just viewed it on 2 different laptops. One is on Vista and One is on XP pro, it identified both and the correct IPs

[Cabdullahi]

integrate x4

[Yanal]

^:?

[Cabdullahi]

answer...is sweet young brother x5/5 +c

[Whatsthepoint]

answer...is sweet young brother x5/5 +c

Ok, now integrate x on -1 power.

[~Raynn~]

Ok, now integrate x on -1 power.

Lol, that would be lnx

:D

[~Raynn~]

answer...is sweet young brother x5/5 +c

Of course, can't forget the constant! :giggling:

How about differentiating e^x??

[Whatsthepoint]

Lol, that would be lnx

:D

WRONG!!!!!!!!!!!!!!!!!!!
lnx + C:)
And I was asking JUNIOR.:raging:
Ok, integrate tangx.

[Yanal]

Which grade math is this?

[Whatsthepoint]

Of course, can't forget the constant! :giggling:

How about differentiating e^x??

(e^x)dx

[Whatsthepoint]

Which grade math is this?

Way above you, kiddo.
Go play with crayons or something.

[Yanal]

^ thats not nice I'm in grade---- almost triple digit:D

[transition?]

Way above you, kiddo.
Go play with crayons or something.

Lol ouch. I'll take great offense to this even if he doesn't.
Loads of 15/16 years old take Calculus.

[transition?]

WRONG!!!!!!!!!!!!!!!!!!!
lnx + C:)
And I was asking JUNIOR.:raging:
Ok, integrate tangx.

I hate C with a passion more than I hate forgetting to add the (-) negative sign when I write down the answer.

[~Raynn~]

Lol!! Calculus rocks!

WRONG!!!!!!!!!!!!!!!!!!!
lnx + C:)

I know, I knowww... I remembered later and couldn't change it! :heated:

And I was asking JUNIOR.:raging:
Ok, integrate tangx.

:-[ I couldn't resist, lol...can I do this one??

And lol, I so agree, the c is totally annoying...

[The Ruler]

Forming the differential equations is more fun and exciting.

[GreyKode]

What is tangx?
do you mean tanhx?

[Whatsthepoint]

What is tangx?
do you mean tanhx?

I meant tanx.

[transition?]

What is tangx?
do you mean tanhx?

I was wondering that, too.

I am under the impression that most mathematical notation is uniform throughout the world.
I once went to an Indian School, although the school was English based, they called some of their concepts by different names!

[Whatsthepoint]

I was wondering that, too.

I am under the impression that most mathematical notation is uniform throughout the world.
I once went to an Indian School, although the school was English based, they called some of their concepts by different names!

It's not entirely uniform.

[transition?]

Calculus gets more and more gross the higher you get. +o(

[GreyKode]

ln(sec(x))

[transition?]

It's not entirely uniform.

Oh yeah, I just wonder if most is though.

[transition?]

I had a request for anyone who knows any good Calculus 2 and 3 textbooks I could order. My textbook is obviously fail aka completely incoherent.

[transition?]

I was just wondering if I want to be a biologist/research scientist. Up to what level math do you guys suppose I would need?

[Whatsthepoint]

Oh yeah, I just wonder if most is though.

It is.
Hmmm, what about places with non-Latin font, how do they write equations?

[Whatsthepoint]

ln(sec(x))

No, it's cos instead of sec.

[GreyKode]

nope, ln(cos(x)) is the integral of -ve tan(x).

[Cabdullahi]

Forming the differential equations, though a little mind-boggling at first, is more fun and exciting.

Want some questions like that Junior?

sure sister
here: sin5x
and
2cos 3x + sin 3x - sec(squared) 3x

[~Raynn~]

I was wondering that, too.

I am under the impression that most mathematical notation is uniform throughout the world.
I once went to an Indian School, although the school was English based, they called some of their concepts by different names!

Yeahh...I can't think of a specific example right now, but I remember noticing that certain conventions used in like, mechanics, differed between here in the UK, and America....but I'm pretty sure the notation of tanhx is the same everywhere, lol (I was under the impression that the h was for hyperbolic? They can't change that!!...)

I was just wondering if I want to be a biologist/research scientist. Up to what level math do you guys suppose I would need?

A molecular biologist?! How cool!! Though I'm pretty sure in depth knowledge of calculus won't be crucial for it, lol...

No, it's cos instead of sec.

Really? I thought it was ln|secx| too...the integral of tanhx is ln|coshx| (+c!), though...

[Whatsthepoint]

nope, ln(cos(x)) is the integral of -ve tan(x).

Hmm, could be, we started on this integral thing only 3 days ago.
what about the ∫f'(x)dx/f(x) = ln|f(x)| + C
so when you have tanx = sinx/cosx, and cos'x=-sinx, so basically you have ∫(-(-sinx/cosx))dx = -ln|cosx| + C
??

[Cabdullahi]

its easier to have a go when you have the table of integrals ...thats what helps me otherwise im no good :(

[transition?]

Yeahh...I can't think of a specific example right now, but I remember noticing that certain conventions used in like, mechanics, differed between here in the UK, and America....but I'm pretty sure the notation of tanhx is the same everywhere, lol (I was under the impression that the h was for hyperbolic? They can't change that!!...)



A molecular biologist?! How cool!! Though I'm pretty sure in depth knowledge of calculus won't be crucial for it, lol...



Really? I thought it was ln|secx| too...the integral of tanhx is ln|coshx| (+c!), though...

That's what I'm hoping!

[Whatsthepoint]

Yeahh...I can't think of a specific example right now, but I remember noticing that certain conventions used in like, mechanics, differed between here in the UK, and America....but I'm pretty sure the notation of tanhx is the same everywhere, lol (I was under the impression that the h was for hyperbolic? They can't change that!!...)
Really? I thought it was ln|secx| too...the integral of tanhx is ln|coshx| (+c!), though...

Chemistry and phyics are much less uniform.
I have no idea what a cosh or tanh is.

[Cabdullahi]

we started on this too bierhoff^

[Whatsthepoint]

we started on this too bierhoff^

:D
And are you enjoying it?

[GreyKode]

-ln(cos(x)) = ln(sec(x)).

[Whatsthepoint]

-ln(cos(x)) = ln(sec(x)).

Yeh makes sense if sec is cos^(-1), but I didn't know that a few psots before sorry.

[Cabdullahi]

yeah its not bad...i need to catch up on differentiation cus i slept on the days the lecturer was teaching it

[Whatsthepoint]

yeah its not bad...i need to catch up on differentiation cus i slept on the days the lecturer was teaching it

what are your plans on further education?

[~Raynn~]

Chemistry and phyics are much less uniform.
I have no idea what a cosh or tanh is.

Yeahh, true...and wellll, they come under 'hyperbolic functions'...differentiating and integrating them is quite similar to with trig functions, but they're totally different in most other ways...don't worry about them until you have to, lol...

[GreyKode]

Sorry guys if I interrupted a tutoring course for someone here or anything, I thought it was a general quiz, I didn't follow the whole thread.
Anyways I would be glad to help out in math related problems.

[Cabdullahi]

what are your plans on further education?

hopefully to pass this year inshallah ........but i need to overcome laziness and that i open books and study more often....this the only way i could pass and if i dont fix up ...then off to the jobcentre plus :(

[Whatsthepoint]

hopefully to pass this year inshallah ........but i need to overcome laziness and that i open books and study more often....this the only way i could pass and if i dont fix up ...then off to the jobcentre plus :(

Yeah, but what do you want to do in life?

[Cabdullahi]

just to find a halal job....in the it sector or the networking sector

[Whatsthepoint]

just to find a halal job....in the it sector or the networking sector

So you're not going to uni?

[Cabdullahi]

i am at uni

[Whatsthepoint]

i am at uni

oh, ok.
I'm not there yet.

[arabianprincess]

math maTH MATHHHHHHHHHHH ... horrible memories when it came to studying but thak god i MADE IT.. anyways im gonna be taking math next semester to get it outta the WAY .. so yall will expect many Q's to come .. n i hope yall will help me .. so i might be too much lol but i do need help in this area.. it normally ends me up with a headache.. i cant understand how ppl enjoy it.anywayz thank GOD we have a math corner YAY .. thanks to who ever came up with SUCH A WONDERFULLLLLLL idea.. :))))

[Yanal]

Whatsthepoint,if you're not in UNI you should be playing with pencil crayons. :D anyway which grade does calcus really start?

[Whatsthepoint]

Whatsthepoint,if you're not in UNI you should be playing with pencil crayons. :D anyway which grade does calcus really start?

Wehre I live we don't have these names, it's just maths.

[Tony]

eh!!!!!!!! stumbled in here expecting to see something about numbers, seem to have inadvertantly witnessed some sort of alien language. my head hurts im off to the non genius end of the forum:-[

[Tony]

Thats the funniest thing I heard on this forum so far:D:D:D:D:D:D:D

[~Raynn~]

You're a brother - you're not allowed access to the sisters' section. :-[

Muhahahaha.

:ooh: ...... :offended:

(lol!)

[Musaafirah]

Whatsthepoint,if you're not in UNI you should be playing with pencil crayons. :D anyway which grade does calcus really start?

It's quite funny, I only started calculus in year 10..was about 14/15ish. When are you expected to start calculus in the states do you know?

[The Ruler]

Although I've forgotten most of it now, I use to love calculus.

You're a brother - you're not allowed access to the sisters' section. :-[

Muhahahaha.

That's why it's a place where you feel at home and I feel out of place.

Can someone do this:

Show that the integral of 1/(1+x^2) dx between the limits of 1 and 0 = pi/4 [Let x = tan u]

Integration by subtitution. I hate that part of it.

[~Raynn~]

Sure....though it's gonna be like impossible to understand in this format...

if x = tan u, dx/du = sec^2 u --> dx = sec^2 u du

and 1 + x^2 = 1+tan^2 u = sec^2 u

So, the integral of 1/(1+x^2) dx
= integral of (1/sec^2 u) dx
= integral of (1/sec^2 u)*sec^2 u du
= integral of 1 du = [u]

If the limits of the original integral (in x) were 0 and 1, and x = tanu --> u=invtan x.
The limits of the new integral are invtan(0) = 0, and invtan(1) = pi/4.

Putting these limits for [u] gives [(pi/4) - (0)] = pi/4.

Voila!

[The Ruler]

If the limits of the original integral (in x) were 0 and 1, and x = tanu --> u=invtan x.
The limits of the new integral are invtan(0) = 0, and invtan(1) = pi/4.

Ah, I see... That's where I messed up.

[Yanal]

Dude do some math understandable for all suitable ages or put the title as 18+ only.

[~Raynn~]

I seee....the limits are definitely the most annoying part of integration by substitution, lol...

[The Ruler]

Okay... Here's another one that I got stuck on. And I also tried it several times in several ways but never got to the answer at the back of the book:

The integral of x/(2x+5)^1/2 between the limits of 10 and 2
Let u^2 = (2x+5)

Again, integration by substitution. And the answer at the back of the book = 34/3.

[~Raynn~]

Okey dokey...

Firstly, u^2 = (2x+5) so u =sqrt(2x+5).
Therefore, du/dx = (2x+5)^-0.5 = 1/sqrt(2x+5) --> dx = sqrt(2x+5) du = u du

If the limits of the original integral, in x, are 10 and 2, the integral in u has the limits sqrt(2(10)+5) = 5, and sqrt(2(2)+5) = 3.

Also, we need to rearrange u^2 = (2x+5) to get x = 0.5(u^2-5), which we also substitute into the integral.

The integral of x/(2x+5)^1/2 dx therefore simplifies to the integral of (0.5(u^2-5))/u * u du, which is [0.5((u^3)/3 - 5u)]. I'm skipping a few steps, but evaluate this between the limits 5 and 3, and you'll get 34/3...

[The Ruler]

I had to do that on paper before it was clear. But thanks anyway.

Are there any particular times when you do du/dx rather than dx/du when substituting? Does it make a difference?

[Tony]

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!:exhausted

[Whatsthepoint]

Okey dokey...

Firstly, u^2 = (2x+5) so u =sqrt(2x+5).
Therefore, du/dx = (2x+5)^-0.5 = 1/sqrt(2x+5) --> dx = sqrt(2x+5) du = u du

If the limits of the original integral, in x, are 10 and 2, the integral in u has the limits sqrt(2(10)+5) = 5, and sqrt(2(2)+5) = 3.

Also, we need to rearrange u^2 = (2x+5) to get x = 0.5(u^2-5), which we also substitute into the integral.

The integral of x/(2x+5)^1/2 dx therefore simplifies to the integral of (0.5(u^2-5))/u * u du, which is [0.5((u^3)/3 - 5u)]. I'm skipping a few steps, but evaluate this between the limits 5 and 3, and you'll get 34/3...

Hey lady, are you a mathematician?

[~Raynn~]

I had to do that on paper before it was clear. But thanks anyway.

Are there any particular times when you do du/dx rather than dx/du when substituting? Does it make a difference?

I'm sorry, yeah, I squeezed several steps into one line...and nope, it doesn't make any difference (and anyway, du/dx is just 1/(dx/du))....but if you're given an expression for the substitution in the form x = [something]u (like x = tanu) then it's more natural to keep it that way, and find dx/du.....if instead, you have u = (some expression in x), you'd just find du/dx...

Hey lady, are you a mathematician?

:giggling: Welllllll, I do A level maths and further maths...does that count?? :D

[Banu_Hashim]

*Whoosh!*

^That is the sound of Rayyn's mathematics going straight over my head.

[~Raynn~]

Lol, honestly, it's not that bad!!

[Yanal]

^ math hard I'm almost failing,and thats saying something.

[Banu_Hashim]

^^
Hahahaha...whatever you say!

[Yanal]

Sister Raynn ,what do you learn in A math? Are A levels in Canada?

[Banu_Hashim]

In the UK bro. You do it between the ages of 16-18

[~Raynn~]

Sister Raynn ,what do you learn in A math? Are A levels in Canada?

You do a little of everything in A-level math...more algebra, more geometry, lots and lots of calculus...and you have to do applied modules (in statistics or mechanics or something) too...

And yup, A levels are specific to the UK...hmm, I don't know about the system in Canada...

[Yanal]

Need help today! How do u do percent? Like 28% of 897? Please explain in simple words.

[Woodrow]

Need help today! How do u do percent? Like 28% of 897? Please explain in simple words.

First change the % to a decimal.

28%=.28

Now multiply 897 x .28


897
x.28
07176
17840
250.16

[Woodrow]

First change the % to a decimal.

28%=.28

Now multiply 897 x .28


897
x.28
07176
17840
250.16

Another way, which may be how your teacher is explaining it would be to multiply 897 x 28 and divide by 100

897 x 28= 25016


25016 divided by 100 =250.16

[Yanal]

JazakAllah how bout 70% of a number is 49.

[Woodrow]

JazakAllah how bout 70% of a number is 49.

This you do in the opposite order. However to avoid confusion I will use 20% of a number is 49.

20% means 20 parts per 100

divide 100 by 20

OOOOps20 divided by 100 that was supposed to be-- 100 divided by 20 = 5

49 is one part of the full 100% there are 5 parts to make 100%

Multiply 49 x 5 that equals 245 for your answer.

Now you try it with the 70% the answer will surprise you.

[Abdu-l-Majeed]

JazakAllah how bout 70% of a number is 49.

Always use a suitable notation. Writing down things can make the things very easy.

[transition?]

It's quite funny, I only started calculus in year 10..was about 14/15ish. When are you expected to start calculus in the states do you know?

I believe they start calculus your third or fourth(the last) year in high school. So I'd say mainly 16/17/18 ish. On that note, I'm surprised you started at 14/15!

It really depends though which math track you're on. Some people are quite blessed, they go on a faster track. Others don't touch a real calculus until they've graduate their fourth year in high school and gone to a university.

[transition?]

:sl:

lol, on a good note, once you do get into higher level math, computers and these ginormous calculators do your triple integrals for you =) !!!

[~Raynn~]

^ Lol, exactly!

At present, we're doing this module entitled 'decision maths'...it basically involves using loads of different (usually pointless, and always ridiculously time-consuming) algorithms to, for example find the shortest path from one place to another, or match things together in the best way possible...and there's actually even an algorithm for putting numbers in ascending order, :rolleyes:. As if any of this would ever be done by hand...

(And also - to add to the percentages stuff - yup, using the right notation makes everything so much easier. It's important to be able to change a worded question into an equation you can solve...like, where it says %, you write /100....and the word 'of' means multiply...so 28% of 897 is just 28/100 * 897, etc...)

[Mysterious Uk]

I'm doing a placement in a primary school and their way of subtraction has changed a lot since my day. They do it in the form of partitions and exchange so

67-39=

60-30 7-9 can't do that so you borrow 10 from 60 and add to 7 so..
50-30= 20 17-9= 8

20+8= 28 so 67-39= 28

This is a method used by year 3's or 7-8 year olds lol It is an interesting method lol thought i'd share it.

[The Ruler]

^I taught the gool ol' borrowing. My teacher, I remember, made each borrowing like one shopkeeper borrowing vegetables from the other. That was, I suppose, our first lesson in business and trade too.

[The Ruler]

Parametric differentiation:

- The parametric equations of a curve are x = asin t, y = a cos^2 t, 0</= t </=pi/2

I differentiated x to get sint + acost. Is that even right?
Then substituted cos^2 t with 1/2(cos2t + 1)

Then got y = 1/2a(cos 2t + 1)
Then differentiated that to get:
1/2(cos2t + 1 - 1/2asin 2t).

I stopped there because I doubt that's right.

[GreyKode]

I think it should be
x=asin(theta) , y=acos^2(theta)

[The Ruler]

Of course. My bad.

[GreyKode]

Then got y = 1/2a(cos 2t + 1)
Then differentiated that to get:
1/2(cos2t + 1 - 1/2asin 2t).

????
d/dt(y) simply = -2(cos(t))(sin(t))

[The Ruler]

Why was the 'a' not taken into account?

EDIT: Ah... I see my mistake. I ended up integrating parts. But I still don't understand about the 'a'

[GreyKode]

sorry..lol
The a is just a constant...
d/dt(y) simply = -2a(cos(t))(sin(t))

I hope I've cleared up the confusion

[The Ruler]

Yes, you have. I was treating 'a' as some sort of unknown number. Tch.

[Banu_Hashim]

Is this C4?

[The Ruler]

Yes.

[Musaafirah]

I believe they start calculus your third or fourth(the last) year in high school. So I'd say mainly 16/17/18 ish. On that note, I'm surprised you started at 14/15!

It really depends though which math track you're on. Some people are quite blessed, they go on a faster track. Others don't touch a real calculus until they've graduate their fourth year in high school and gone to a university.

You're saying the final years of high school right? Years 10/11 are our final years, though I covered calculus in more detail when I studied for A-level Maths.
And promptly forgot everything. :D

[The Ruler]

I think I did a fantastic job with Paint. I'm rather proud of what I've done. Anyway... I have no clue where to start or what to do.

And I just noticed that the actual question seems to have an 'O' instead of 'y' in the y-axis. So, I suppose, it's an O-axis now.

[~Raynn~]

Lol, wow, that IS a pretty amazing graph...

Okayy, you start by finding dy/dx; use the product rule...you get:

dy/dx = 2tan2x + (2x-1)(2sec^2(2x)) = 2tan2x + 4xsec^2(2x) - 2sec^2(2x)

At the stationary point P, x = k, and dy/dx = 0, so set the above expression ^^ to equal zero, and replace x with k:
2tan2k + 4xsec^2(2k) - 2sec^2(2k) = 0

Multiply throughout by cos^2(2k) - or divide by sec^2(2k) - to get:

2(cos^2(2k))(tan2k) + 4k - 2 = 0
2(cos2k)(sin2k) + 4k - 2 = 0 .......[because cosxtanx = sinx, so cos^2xtanx = cosxsinx]
sin4k + 4k - 2 = 0 ........[double angle formula for sinx]
Therefore 4k + sin4k - 2 = 0

[The Ruler]

Difficult stuff indeed. But maybe that's because I'm mesmerised by my art to focus on the differentiation. I think I'll take a break and then come back.

[Whatsthepoint]

x satisfies this equation
cos(2x) + cos(3x) = 1
Show that it also satisfies this one:
2sin(2x) + 2sin(3x) = sin(4x) + 2sin(5x) + sin(6x)

hEr's one for ya, Raynn