(y+z-2x)^2+(z+x-2y)^2+(x+y-2z)^2-3(y-z)^2-3(z-x)^2-3(x-y)^2_数学解答

(y+z-2x)^2+(z+x-2y)^2+(x+y-2z)^2-3(y-z)^2-3(z-x)^2-3(x-y)^2

人气：349 ℃　时间：2020-01-29 13:56:48

解答

令a=y-zb=z-xc=x-y原式=(b-c)²+(c-a)²+(a-b)²-3a²-3b²-3c²=b²-2bc+c²+c²-2ac+a ²+a²-2ab+b²-3a²-3b²-3c²-(a²+b²+c²+2a...