题目内容：

已知3的m次方=6,3的n次方=5,求3的2m-3n方

优质解答

已知,3^m = 6 ,3^n = 5 ,
可得：3^(2m-3n) = 3^(2m)/3^(3n) = [(3^m)^2]/[(3^n)^3] = 6^2/5^3 = 36/125 .