Question

What are the zeros for x^3-6x^2-31x+120

Answer 1

Explanation:

x³-6x³-31x+120=0

x³-3x²-3x²+9x-40x+120=0

x²(x-3)-3x(x-3)-40(x-3)=0

(x-3)(x²-3x-40)=0

(x-3)[x²-8x+5x-40]=0

(x-3)[x(x-8)+5(x-8)]=0

(x-3)(x-8)(x+5)=0

x-3=0,x=3

x-8=0,x=8

x+5=0

x=-5

zeros are,-5,3,8