Question 195803
Factor:
{{{27b^4-64b}}} First, factor a (b) to get:
{{{b(27b^3-64)}}} Notice that the parentheses contain the difference of cubes.
{{{b((3b)^3-(4)^3)}}}
The difference of cubes factors thus: {{{A^3-B^3 = (A-B)(A^2+AB+B^2)}}}, so...
{{{b((3b)^3-(4)^3) = highlight(b(3b-4)(9b^2+12b+16))}}}