How do you factor completely: #4x^3 - 8x^2 - 26x + 50#?

1 Answer
Jul 23, 2015

As written, it cannot be factored by the methods taught in pre-caculus level algebra classes. If the 26 was supposed to be 25, then factor by grouping.

Explanation:

Answer 1
If you can find the roots using the cubic formula (nost of us do not have that formula memorized), then you can factor.

Answer 2

If there is an eror in the question, and the intended question is:

How do you factor completely: #4x^3 - 8x^2 - 25x + 50#?

Then you can factor by grouping (and the difference of squares):

# 4x^3 - 8x^2 - 25x + 50 = (4x^3 - 8x^2)+( - 25x + 50)#

# = 4x^2 (x - 2)+(-25)(x-2)#

# = (4x^2-25) (x - 2)#

# = (2x+5)(2x-5)(x-2)#