(3m+2n)的平方-(5m-2n)的平方
=(3m+2n+5m-2n)(3m+2n-5m+2n)
=8m*(-2m+4n)
=-16m*(m-2n)
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(3m+2n)的平方-(5m-2n)的平方
=[﹙3m+2n﹚+﹙5m-2n﹚][﹙3m+2n﹚-﹙5m-2n﹚]
=﹙3m+2n+5m-2n﹚﹙3m+2n-5m+2n﹚
=10m﹙4n-2m﹚
=20m﹙2n-m﹚
(3m+2n)的平方-(5m-2n)的平方
=(3m+2n+5m-2n)(3m+2n-5m+2n)
=8m(4n-2m)
=16m(2n-m)
=(3m+2n+5m-2n)(3m+2n-5m+2n)
=8m(-2m+4n)
=-16m(m-2n)
此题用平方差公式做(3m+2n)的平方-(5m-2n)的平方 =(3m+2n+5m-2n)(3m+2n-5m+2n) =8m(4n-2m) =16m(2n-m)望采纳