=2
因为x+y=2z
所以【x-z=z-y】
所以原式=x/(z-y)-y/(z-y)
=(x-y)/(z-y)
=(x-y)/(x-z)
=(x-z+z-y)/(x-z)
=1+(z-y)/(x-z)
=1+(z-y)/(z-y)
=1+1
=2
=2
因为x+y=2z
所以【x-z=z-y】
所以原式=x/(z-y)-y/(z-y)
=(x-y)/(z-y)
=(x-y)/(x-z)
=(x-z+z-y)/(x-z)
=1+(z-y)/(x-z)
=1+(z-y)/(z-y)
=1+1
=2