2.1.1 指数综合一、复习引入:1根式的运算性质:当n为任意正整数时,.)(aa nn当n为奇数时,nna=a;nna)0()0(aaaa当n为偶数时,=|a|=2.正数的正分数指数幂的意义:)1*,0(nNnmaaanmnm且5分数指数幂的运算性质:)()(),()(),(QnbaabQnmaaQnmaaannnmnnmnmnm3.负分数指数幂:)1*,0(1nNnmaaanmnm且4.0的正分数指数幂等于0,0的负分数指数幂没有意义二、讲解范例:例1.计算下列各式(式中字母都是正数)88341656131212132)(2()3()6)(2)(1(nmbababa例2.计算下列各式.)0()2(25)12525)(1(32243aaaa例3.求值:63125.132)2(;246347625)1(例4 写出使下列等式成立的x的取值范围:3131)1(33xx5)5()25)(5()2(2xxxx1例5画出函数323213312xxxxxy的图象。例6 已知x+x-1=3,求下列各式的值:.)2(,)1(23232121xxxx32)3(222323xxxx例7.化简)()(1(41412121yxyx)41()3)(2)(2(324132213141bababa三、课后作业:课本第82页 A组1,2补充已知:63232dcba求证:)1)(1(1)(1(cb)da