How do you factor 4b^3 +3b^2-16b-12?

2 Answers
May 5, 2015

Regroup to maximize the extractable factors
4b^3+3b^2-16-12 = color(red)(4b^3-16b) + color(blue)(3b^2-12)

=color(red)(4b(b^2-4)) + color(blue)(3(b^2-4))

=(4b+3)(b^2-4)

Recognize the second term as the Difference of Squares
=(4b+3)(b+2)(b-2)

May 5, 2015

Collect 4b between the first and third term and +3 between the second and rourth:
4b(b^2-4)+3(b^2-4)= collect (b^2-4)
(b^2-4)(4b+3)