通分2mn/4m²-9与2m-3/2m+3
问题描述：
通分2mn/4m²-9与2m-3/2m+3
答
4m²-9=(2m+3)(2m-3)
所以最简公分母就是4m²-9
所以(2m-3)/(2m+3)=(2m-3)²/(4m²-9)