Don't Forget About These

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by sureshbala » Sat May 09, 2009 4:02 am
If x^2 - x divides P(x) = x^4 - x^3 + x^2 + ax + b, then find the value of a+b.

Given x^2 - x divides P(x).

i.e. x(x-1) divides P(x).

i.e. x-1 divides P(x) [P(x) will be divisible by x if b is divisible by x.]

Hence P(1) = 0

i.e. 1 - 1 + 1 + a + b = 0

Hence a + b = -1