已知x的m次方=3,x的n次方=4 求(1)x的m+n次方 (2)x的3m次方 (3)x的3m+2n次方
解:(1)x的m+n次方
=x^m*x^n
=3*4
=12
(2)x的3m次方
=3^3
=27
(3)x的3m+2n次方
=3*3*3*4*4
=27*16
=432 .