0.76*23+7.6*2.2+5.5*7.6 654321的平方-654322*654320 128*132

0.76×23+7.6×2.2+5.5×7.6=0.76×23+0.76×22+55×0.76……变一变,就简便.=0.76×（23＋22＋55）=0.76×100=76654321²-654322×654320 =654321²－（654321＋1）×654320=654321²－654321×654320－...