(x+y-z)*(x+y-z)-(x-y+z)*(x-y-z)等于多少
问题描述:
(x+y-z)*(x+y-z)-(x-y+z)*(x-y-z)等于多少
答
你好 (x+y-z)*(x+y-z)-(x-y+z)*(x-y-z)=[(x+y)-z]*[(x+y)-z]-[(x-y)+z]*[(x-y)-z)]=[(x+y)²-z²]-[(x-y)²-z²]=(x+y)²-(x-y)²=4xy 【数学辅导团】为您解答,不理解请追...