(m-n)(3m-n)²+(m+3n)²(n-m)今晚就要!帮帮偶!

(m-n)(3m-n)²+(m+3n)²(n-m)今晚就要!帮帮偶!
(m-n)(3m-n)²+(m+3n)²(n-m)
今晚就要!帮帮偶!

(m-n)(3m-n)²+(m+3n)²(n-m)今晚就要!帮帮偶!
(m-n)(3m-n)²+(m+3n)²(n-m)
=(m-n)(3m-n)²+[-(m+3n)²(m-n)]
=(m-n)(3m-n)²-(m+3n)²(m-n)
=(m-n)[(3m-n)²-(m+3n)²]
=(m-n)[(3m-n)+(m+3n)][(3m-n)-(m+3n)]
=(m-n)(4m+2n)(2m-4n)
=4(m-n)(2m+n)(m-2n)

(m-n)(3m-n)²+(m+3n)²(n-m)
=(m-n)(3m-n)²-(m-n)(m+3n)²
=(m-n)[(3m-n)²-(m+3n)²]
=(m-n)(3m-n+m+3n)(3m-n-m-3n)
=(m-n)(4m+2n)(2m-4n)
=4(m-n)(2m+n)(m-2n)

原式=（m-n)[(3m-n)^2-(3n-m)^2]

=(m-n)[9m^2-9n^2+n^2-m^2]

=(m-n)[8m^2-8n^2]

=8(m-n)^2(m+n)

=（m-n)(3m-n)^2-(m-n)(m+3n)^2
=(m-n)[(3m-n)^2-(m+3n)^2]
=(m-n)(3m-n+m+3n)(3m-n-m-3n）
=（m-n)(4m+2n)(2m-4n)
=4(m-n)(2m+n)(m-2n）

(m-n)(3m-n)²+(m+3n)²(n-m)
= (m-n)[3m-n)² - (m+3n)²]
= (m-n)(3m-n+m+3n)(3m-n-m-3n)
= (m-n)(4m+2n)(2m-4n)
= 4(m-n)(2m+n)(m-2n)