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# P2 Functions watch

1. 15 + 4x - x² ≡ p - (x-q)²

Find values of p and q for all real values of x. i tried to expand the bracket and tried to solve the LHS
2. 15 + 4x - x² = -(x² - 4x - 15) = -[(x-2)² - 19] = 19 - (x-2)²
3. yer what mockel did, just complete the square
4. (Original post by ThugzMansion7)
15 + 4x - x² ≡ p - (x-q)²

Find values of p and q for all real values of x. i tried to expand the bracket and tried to solve the LHS
i think its completing the square, so u have 2 show dat equation in the completed square form-the x² is minus so rewrite equation

-x²+4x-15=0
this gives -(x-2)²=0
this equals -x²+4x-4=0
so to get to the first equation all you have to do is
-(x-2)²+19=0

so p=19 and q=-2
(i think so neway! )
so p=19 and q=-2
(i think so neway! )
You just have to be a little careful with the way you give your final answer, since the desired answer is in the form:
p - (x-q)²,

so q = 2, rather than -2...

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