(m+n)(m-n)(-m的2次方-n的2次方)化简

问题描述:

(m+n)(m-n)(-m的2次方-n的2次方)化简

(m+n)(m-n)(-m的2次方-n的2次方)
=-(m²-n²)(m²+n²)
=-(m四次方-n四次方)