How do you factor # y = x^3 -10x -12#?

1 Answer
Oct 9, 2015

Answer:

Factor #y = x^3 - 10x - 12#

Ans: #y = (x + 2)(x^2 - 2x - 6)#

Explanation:

Substitute x = -2 into the function, we get f(-2) = 0. Then (x + 2) is a factor.
By division, we get:
#y = (x + 2)(x^2 - 2x - 6)#
The trinomial can't be factored because its D = 4 + 24 = 28 is not a perfect square.
Therefor: #y = (x + 2)(x^2 - 2x - 6)#