Question

Simplify. (-m-3n)^3-(m-3n)^3​

Answer 1

Answer: $-2m^3-54mn^2$

Step-by-step explanation:

$\left(-m-3n\right)^3-\left(m-3n\right)^3$

$=\left(-m^3-9m^2n-27mn^2-27n^3\right)-\left(m-3n\right)^3$

$=\left(-m^3-9m^2n-27mn^2-27n^3\right)-\left(m^3-9m^2n+27mn^2-27n^3\right)$

$=\left(-m^3-9m^2n-27mn^2-27n^3\right)-m^3+9m^2n-27mn^2+27n^3$

$=-2m^3-54mn^2$