化简m/(m+n)²+n/m²-n²-2n²/(m+n)(m²-n²﹚

问题描述:

化简m/(m+n)²+n/m²-n²-2n²/(m+n)(m²-n²﹚

m/(m+n)²+n/(m²-n²)-2n²/(m+n)(m²-n²)
=[m(m²-n²)+n(m+n)²-2n²(m+n)]/[(m+n)²(m²-n²)]
=[m(m²-n²)+(nm+n²-2n²)(m+n)]/[(m+n)²(m²-n²)]
=[m(m²-n²)+(nm-n²)(m+n)]/[(m+n)²(m²-n²)]
=[m(m²-n²)+n(m-n)(m+n)]/[(m+n)²(m²-n²)]
=[m(m²-n²)+n(m²-n²)]/[(m+n)²(m²-n²)]
=[(m+n)(m²-n²)]/[(m+n)²(m²-n²)]
=1/(m+n)

m/(m+n)²+n/(m²-n²)-2n²/[(m+n)(m²-n²﹚]
=m(m-n)/[(m+n)²(m-n﹚]+n(m+n)/[(m+n)²(m-n﹚]-2n²/[(m+n)²(m-n﹚]
=(m²-mn+mn+n²-2n²)/[(m+n)²(m-n﹚]
=(m²-n²)/[(m+n)(m²-n²﹚]
=1/(m+n)

楼主所给式子,是m/(m+n)²+n/(m²-n²)-2n²/[(m+n)(m²-n²)] 如果是的话:m/(m+n)²+n/(m²-n²)-2n²/[(m+n)(m²-n²)]=m/(m+n)²+n/[(m-n)(m+n)]-2n²...