Question

Find a cubic function with the given zeros.

√2, -√2 , -2

a.f(x) = x3 + 2x2 - 2x + 4

b.f(x) = x3 + 2x2 + 2x - 4

c.f(x) = x3 - 2x2 - 2x - 4

d.f(x) = x3 + 2x2 - 2x - 4
Please help!!!!!!

Answer 1

@eSpeX

Answer 2

For this problem I would start by reminding you that the roots occur at your 'x' values. So if your 'a' term were equal to 0, you would have a quadratic equation, if your 'd' term were equal to 0 you could factor out an 'x' and have a quadratic equation. If your 'b'='c'=0, you would have a simple algebraic equation.
Using this information I would work backwards and prove the roots.