数学分式化简求值题1/x - 1/y = 3 的时候求 2x + 3xy - 2y/x - xy -y 的值
1个回答
1/x - 1/y = ( x - y )/xy=3
x-y=3xy
2x + 3xy - 2y/x - xy -y=(6xy+3xy)/(3xy-xy)=9/2
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