How do you factor # 125x^3+64#?
1 Answer
Dec 14, 2015
Use the sum of cubes identity to find:
#125x^3+64=(5x+4)(25x^2-20x+16)#
Explanation:
Both
#a^3+b^3=(a+b)(a^2-ab+b^2)#
With
#125x^3+64#
#=(5x)^3+4^3#
#= (5x+4)((5x)^2-(5x)(4)+4^2)#
#=(5x+4)(25x^2-20x+16)#