(1)36(x+y)二次-49(x-y)二次(2)(x+y)二次/4-(x-y)二次/4

(1)36(x+y)二次-49(x-y)二次(2)(x+y)二次/4-(x-y)二次/4


(1)36(x+y)二次-49(x-y)二次=【6(x+y)】平方-[7(x-y)]平方=[6(x+y)+7(x-y)][6(x+y)-7(x-y)]=(6x+6y+7x-7y)(6x+6y-7x+7y)=(13x-y)(13y-x)(2)(x+y)二次/4-(x-y)二次/4=1/4 [(x+y)平方-(x-y)平方]=1/4(x…