Question

What are the factors for `128m-2m^4`?

Answer 1

`128m-2m^4 = 2m(4^3-m^3)`

`= 2m(4-m)(4^2+4m+m^2)`

`=2m(4-m)(16+4m+m^2)`

...using the difference of cubes identity

`a^3 - b^3 = (a-b)(a^2+ab+b^2)`

There are no simpler factors with real coefficients.