What are the roots of x3 minus 3x2minus9x minus 5 equals 0?

Answer 1

x3 - 3x2 - 9x - 5 = 0

(x + 1)(x2 - 4x - 5) = 0

(x + 1)(x - 5)(x + 1) = 0

x ∈ {-1, 1, 5}