1-(x-y)/(x-2y)+(x^2-y^2)/(x^2-4xy+4y^2)实数x,y满足|2x-y+1|+2根号下3x-2y+4=0化简求值 刚才题打错了

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1-(x-y)/(x-2y)+(x^2-y^2)/(x^2-4xy+4y^2)实数x,y满足|2x-y+1|+2根号下3x-2y+4=0化简求值 刚才题打错了

1-(x-y)/(x-2y)+(x^2-y^2)/(x^2-4xy+4y^2)实数x,y满足|2x-y+1|+2根号下3x-2y+4=0化简求值 刚才题打错了
1-(x-y)/(x-2y)+(x^2-y^2)/(x^2-4xy+4y^2)实数x,y满足|2x-y+1|+2根号下3x-2y+4=0化简求值 刚才题打错了

1-(x-y)/(x-2y)+(x^2-y^2)/(x^2-4xy+4y^2)实数x,y满足|2x-y+1|+2根号下3x-2y+4=0化简求值 刚才题打错了
即2x-y+1=0
3x-2y+4=0
所以x=2,y=5
所以原式=1-(x-y)/(x-2y)+(x^2-y^2)/(x-2y)^2
=(x^2-4xy+4y^2-x^2+3xy-2y^2+x^2-y^2)/(x-2y)^2
=(x^2-xy+y^2)/(x-2y)^2
=(4-10+25)/(2-10)^2
=19/64