Question

find all the zeroes of the polynomial x³+3x²-2x-x if 2

Answer 1

Lets try (-1)
p(x) = x^3+3x^2-2x-x
p(-1) = (-1)^3+ 3(-1)^2- 2(-1) - (-1)
= -1+3+2+1
=5
=> x=-1 is not a zero of p(x)

Lets try (1)
p(x) = x^3+ 3x^2- 2x-x
= (1)^3 +3(1)^2 - 2(1) -(1)
= 1+3-2-1
= 1
=> x=1 is not a zero of p(x)

Lets try (5)
p(x) = x^3 + 3x^2 - 2x - x
= (5)^3 + 3(5)^2 - 2(5) - (5)
= 125 + 75 - 10 - 5
= 200 -15
=185