当x=2分之1,y=-4时(xy-x的平方)÷xy分之x-ygoodpeople_数学解答

当x=2分之1,y=-4时(xy-x的平方)÷xy分之x-y
goodpeople

人气：249 ℃　时间：2020-06-02 03:22:30

解答

(xy-x²)÷(x-y)/xy
=-x(x-y)÷(x-y)/xy
=-x(x-y)×xy/(x-y)
=-x²y
∵x=1/2,y=-4
∴原式=-1/4×(-4)=1