# math

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Consider the function f(x)=x^3+4x^2+kx-4. The remainder from f(x)/(x+2) is twice the remainder from f(x) / (x-2). Determine the value of k

• math -

A little synthetic division yields:

f(x) = (x+2)(x^2+2x+k-4) + (-4-2k)
f(x) = (x-2)(x^2+6x+k+12) + (2k+20)

-4-2k = 2k+20
k = -6

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