For the polynomial P(x)=x3−5x2+2x+8P(x) = x^3 - 5x^2 + 2x + 8P(x)=x3−5x2+2x+8, which of the following is NOT a root?
x=−1x = -1x=−1
x=2x = 2x=2
x=4x = 4x=4
x=1x = 1x=1