幂的乘方,根据乘方的意义及同底数幂的乘法填空，看看计算的结果有什么规律：(32)3=323232=3( );(a2)3=a2a2a2=a ( ).(am)3=amamam=a( ) (m是正整数).,探究,(am)n=amn(m,n都是正整数),即幂的乘方,底数不变,指数相乘.,例2:计算: (1) (103)5; (2) (a4)4; (3) (am)2; (4) -(x4)3.,解: (1) (103)5=1035 = 1015 ; (2) (a4)4=a44=a16; (3) (am)2= a m 2 = a 2m ; (4) -(x4)3 = - x 43 = - x12 .,例题,计算：(103)3; (2) (x3)2; (3) - ( xm )5 ; (4) (a2 )3 a5;,练习,1. 已知, 4483=2x, 求x的值.,2. 试比较3555, 4444, 5333的大小.,再见,
