先化简再求值练习题先化简再求值练习题 21m1、化简:,, 2mm,,93 2aa,12a2、化简: ()? -a,1a,1a 32xxx,,3、先化简,再求值:,其中( ,,x,,45,,2xxx,,,224,, 2a,3aa,32,,4、先化简,再求值:,其中a,2,2( 2a,2a,2a,4a,4 11b,,,5、先化简,再求值:?,其中, a,1,2b,1,2,,22abab,,aabb,,2,, 2xxxx,,,3216、先化简,再求值: ,其中( x,,21,2xxx,,,113 2xx,,447、先化简,再求值:...