Find the roots of this polynomial equation

x^3-2x^2+10x+136=0

x³ - 2x² + 10x + 136 = 0

x³ - 6x² + 4x² + 34x - 24x + 136 = 0

x³ - 6x² + 34x + 4x² - 24x + 136 = 0

x (x²) - x (6x) + x (34) + 4 (x²) - 4 (6x) + 4 (34) = 0

x (x² - 6x + 34) + 4 (x² - 6x + 34) = 0

(x + 4) (x² - 6x + 34) = 0

x + 4 = 0 U x² - 6x + 34 = 0

- 4 - 4 x = - (-6) + / - √ ((-6) ² - 4 (1) (34))

x = - 4 2 (1)

x = 6 + / - √ (36 - 136)

2

x = 6 + / - √ (-100)

2

x = 6 + / - 10i

2

x = 3 + 5i

x = 3 + 5i U x = 3 - 5i

The solution set is equal to {-4, 3 + 5i}.