x的m次方等于5,x的n次方等于3,求x的2m-3n次方求求帮个忙
问题描述：
x的m次方等于5,x的n次方等于3,求x的2m-3n次方
求求帮个忙
答
27分之25
答
x^(2m-3n)=(x^m)^2/(x^n)^3=5^2/3^3=25/27
答
x^(2m-3n)=(x^m)^2/[(x^n)^3]=5²/3³＝25/27
x^(2m-3n)
＝(x^2m)/(x^3n)
＝(x^m)²/(x^n)³
＝5²/3³
＝25/27
答
x^m=5
x^n=3
x^(2m-3n)
=x^(2m)/x^(3n)
=5^2/3^3
=25/27