问题
解答题
分解因式：（m+n）2-（m-n）2．
答案
（m+n）2-（m-n）2
=[（m+n）+（m-n）][（m+n）-（m-n）]
=2m•2n
=4mn．
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分解因式：（m+n）2-（m-n）2．
（m+n）2-（m-n）2
=[（m+n）+（m-n）][（m+n）-（m-n）]
=2m•2n
=4mn．
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