# Maths help: Maths help please! - Help.com

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I’m currently revising for my As C1 Maths Exam, but I’ve just come across a question that I can’t do :(
I’m sure it’s obvious, I just can’t work it out right now…thanks

1) Given that 2x^2 - 12x + p = q(x-r)^2 + 10 for all values of x, find the constants p,q and r.

Also, if anybody could suggest any good ways to revise for English Literature that’d be great, I’m predicted an A, but I can’t think of any ways to revise except for reading the texts over and over again.
Thanks again :)
x

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Well you should just compare coefficients of x on both sides. So immediately you can see that
p = 10
and so
q(x-r)^2 = 2x^2-12x
qx^2 -2rx + r^2 = 2x^2-12x

So
q = 2
and
-2r = 12
therefore
r = -6

Help me with: Insignificance.

^
Also…spark notes?

I’m sorry, but I have the mark scheme, the answers are: q=2, r=3 and p=28. I’m just not sure how to get them x

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Philip Larkin’s collection, The Whitsun Weddings and Tom Stoppard’s Arcadia.

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D:
I keep getting p=14

2x^2 - 12x + p = q(x-r)^2 + 10

2X^2 YOU COMPARE THE COEFF. LIKE BEFORE q(x-r)^2

q=2

Divide both sides by 2

x^2 - 6x + p = (x-r)^2 + 5

expand

x^2 - 6x + p = x^2 - 2xr + r^2 + 5

by comparison
-6x = -2xr

r=3

And

p= r^2 + 5

So p= 3^2 +5
p=14.

>8C

Keckers wrote:
D:
I KEEP GETTING P=14
FGDSHFSGS

Yeah the marks scheme is right; I’, not concentrating. Just expand out the RHS and compare the coefficient and they come out.

Help me with: Insignificance.

**** you I have no idea!!!!!

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