如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少

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如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少

如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少
如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少

如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少
因为x+y=2z
所以x-z=z-y
x-y=2z-2y=2(z-y)
所以 x/(x-z)+y/(y-z)
=x/(x-z)-y/(x-z)
=(x-y)/(x-z)
=2(z-y)/(z-y)
=2

x-z=z-y
x/x-z+y/y-z=(x-y)/x-z
y=2z-x
代入上式的结果为2

x=2z-y代入
x/(x-z)+y/(y-z)=(2z-y)/(z-y)-y/(z-y)=(2z-2y)/(z-y)=2

x+y=2z
x-z=z-y
x+y=2z
z=(x+y)/2,
x/(x-z)+y/(y-z)
=x/[x-(x+y)/2]+y/[y-(x+y)/2]
=x/[(x-y)/2]+y/[(y-x)/2]
=x/[(x-y)/2]-y/[(x-y)/2]
=2x/(x-y)-2y/(x-y)
=(2x-2y)/(x-y)
=2(x-y)/(x-y)
=2

我也在想啊