Question

What are all the zeros of the polynomial
y= -x^3 -3x^2 +6x +8
In synthetic division

Answer 1

x=2, -4, -1

Explanation:

-x³-3x²+6x+8=0

Multiply entire equation by -1:

x³+3x²-6x-8=0

Since x=2 is a solution, then x-2 must be a factor. Then:

x³+3x²-6x-8/x-2=x²+5x+4

x²+5x+4=0

Factor this:

x²+5x+4=(x+4)(x+1)=0

x=-4, -1

x=2, -4, -1