posted by Michael J .
If you want to check your answer, just multiply -4x(6x^3-3x^2-4x). You will find out that you need to check your signs and your division.
this problem is divide by negative 4x
so my answer is should be 6x^3+3x^2+12x^
let me know if this right.
It should be -6x^3+3x^2-12x. You just had a few signs wrong.