化简1/6m-4n-1/6m+4n-3m/4n^2-9m^2
问题描述：
化简1/6m-4n-1/6m+4n-3m/4n^2-9m^2
答
原式=(3m+2n-3m+2n+6m)/2(3m+2n)(3m-2n)
=2(3m+2n)/2(3m+2n)(3m-2n)
=1/(3m-2n)