Question

Упростите

(m^2-n^2/m-n)- (m^3-n^3m^2-n^2)

Answer 1

$frac{m^2-n^2}{m-n}-frac{m^3-n^3}{m^2-n^2}=frac{(m-n)(m+n)}{m-n}-frac{(m-n)(m^2+mn+n^2)}{(m-n)(m+n)}=$

$=(m+n)-frac{m^2+mn+n^2}{m+n}=frac{(m+n)^2-(m^2+mn+n^2)}{m+n}=$

$=frac{m^2+2mn+n^2-m^2-mn-n^2}{m+n}=frac{mn}{m+n}$