Question

Find all integer zeros of the function.
x^4 + x^3 - 3x^2 - x + 2 = 0

Answer 1

x^4 + x^3 - 3x^2 - x + 2
=x^4 + x^3 - 2x^2 - x-x^2 + 2
=x^3(x+1) -2(x^2-1) -x(1+x)
=(x+1)(x^3-2(x-1)-x)
can you go on ?

Answer 2

=(x+1)(x^3-3x+2)
=(x+1)(x^3-x-2x+2)
=(x+1)(x(x^2-1)-2(x-1))
=(x+1)(x-1)(x(x+1)-2)

Answer 3

the roots would be
-1, +1, +1 and -2?

Answer 4

yes

Answer 5

thank you so much!