Question

Given the polynomial f(x)=x⁴+3x³-3x²-x, which of the following is true?

a) (x+1) is a factor since f(-1)=0.

b) (x-1) is a factor since f(-1)=0.

c) (x+1) is a factor since f(1)=0.

d) (x-1) is a factor since f(1)=0.​

Answer 1

The answe is b because I did this already