one zero is given. List all zeros of the polynomials.?

Question

one zero is given. List all zeros of the polynomials

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Answer 1

Let p(x) = x³ + x² -4x - 24
First, p(x) must have 3 roots.
Second, if -2 + 2i is a root, so is -2 -2i.
Finally, 3 is a root, since 3³ + 3² -4*3 - 24 = 0.
The roots are -2+2i, -2 -2i and 3.