Author Topic: C2 DOUBT edexcel  (Read 2198 times)

Offline halosh92

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Re: C2 DOUBT edexcel
« Reply #15 on: April 16, 2010, 03:34:54 pm »
A=1, (5+or-sqrt 105)/8

please show workings i need to know how to get da ans

Thanks

which paper is this?
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Amr Fouad

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Re: C2 DOUBT edexcel
« Reply #16 on: April 16, 2010, 03:41:49 pm »
can sme one solve this ques

the coefficient of x3 in the epansion of (2+x)(3-ax)4 is 30
find the values of the constant a.

please show step by step working
Thanks

here u go..:)

@halosh, i answered ur angle question, check the post

Offline halosh92

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Re: C2 DOUBT edexcel
« Reply #17 on: April 16, 2010, 03:46:05 pm »
here u go..:)

@halosh, i answered ur angle question, check the post

 thx AF  but i did the whole thing its correct except when i got stuck at solving the cubic function..how do i do that?
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline past-papers

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Re: C2 DOUBT edexcel
« Reply #18 on: April 16, 2010, 03:51:46 pm »
For C2, you will always get easy cubics and thus you will always be able to find one factor!!

In this case, you can see that if a=1 the equation is equal so you realise that (a-1) is a factor.

now divide by (a-1) and you will get a quadratic which you can easily factorise again...

Offline halosh92

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Re: C2 DOUBT edexcel
« Reply #19 on: April 16, 2010, 03:54:09 pm »
For C2, you will always get easy cubics and thus you will always be able to find one factor!!

In this case, you can see that if a=1 the equation is equal so you realise that (a-1) is a factor.

now divide by (a-1) and you will get a quadratic which you can easily factorise again...

thx aloot ;D ;D
but isnt this a C2 question?
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline past-papers

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Re: C2 DOUBT edexcel
« Reply #20 on: April 16, 2010, 03:57:10 pm »
You tell me :P You asked it haha

It looks like a C2 but it's been more than 2 years since I did C2 so I can't be sure!!

Offline halosh92

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Re: C2 DOUBT edexcel
« Reply #21 on: April 16, 2010, 03:59:59 pm »
You tell me :P You asked it haha

It looks like a C2 but it's been more than 2 years since I did C2 so I can't be sure!!

haha lool no i didnt ask the question someone else did
XD thx alot anyways :) ;D ;D
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Amr Fouad

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Re: C2 DOUBT edexcel
« Reply #22 on: April 16, 2010, 04:06:09 pm »
lool yes past papers is right..

firt you have to find the factors of the constant, in this case 30:

1,30,15,2,5,6,and the negatives of each..

and we know that (a+y) is a factor when f(-y) =0..therefore, a=1 obviously gives us zero,

and so (a-1) is a factor...

do long division, get the quadratic function, and find the solutions..

sorry 4 the late reply, i had to go lol ;D