The Factor Theorem

Question

Use the Factor Theorem to determine whether x - 1 is a factor of P(x) = -2x³ + 4x² - x - 5 .Specifically, evaluate P at the proper value, and then determine whether x - 1 is a factor.

Is x-1 a factor of P(x) or not

P(?) = ?

Answer 1

P(1) = -2 +4 -1 -5 = -4,

x-1 is not a factor, unless P(1)=0

P(-1) = 1 +4 +1 -5 = 1

x+1 is also not a factor, since P(-1) does not equal zero