Thread: Question on Quadratic Application
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Old October 22nd, 2009, 09:13 PM
ukorov ukorov is offline
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y
= x^2 - 2x + k
= x^2 - 2x + (-2/2)^2 - (-2/2)^2 + k
= x^2 - 2x + 1 - 1 + k
= (x^2 - 2x + 1) + (k - 1)
= (x - 1)^2 + (k - 1)
= (x - H)^2 + (K)
where (H,K) is the turning point = (1, -5)
hence -5 = k - 1
k = -4
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