I will assume you mean
x^3 + .9x^2 - .9x = 0
times 10
10x^3 + 9x^2 - 9x = 0
x(10x^2 + 9x - 9) = 0
x = 0 or x = (-9 ± √441)/20
x = 0 or x = (-9 ± 21 )/20
x = 0 or x = .6 or x = -1.5
Solve.
x3 + 0.9x2 − 0.9x = 0
1 answer