Asked by anon

Why is (x-3) not a factor of x^3+2x^2-5x-6?
Answered by Reiny
f(x) = x^3+2x^2-5x-6
if x-3 is a factor , then f(3) = 0

Well, what is f(3)

f(3) = 27 + 18 - 15 - 6 ≠ 0
so x-3 is NOT a factor