Answer:
(x - 1)(3x + 1)(2x + 5)
Explanation:
Given
6x³ + 11x² - 12x - 5
The sum of the coefficients = 6 + 11 - 12 - 5 = 0
Hence x = 1 is a root and (x - 1) a factor
Dividing 6x³ + 11x² - 12x - 5 by (x - 1) using Synthetic division
1 | 6 11 - 12 - 5
↓ 6 17 5
-------------------------
6 17 5 0 ← remainder
Quotient = 6x² + 17x + 5
Thus
6x³ + 11x² - 12x - 5 =(x - 1)(6x² + 17x + 5) = (x - 1)(3x + 1)(2x + 5)