先化简再求值 [(x-y)²+(x+y)(x-y)]÷2x,其中x=3,y=1

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先化简再求值 [(x-y)²+(x+y)(x-y)]÷2x,其中x=3,y=1

先化简再求值 [(x-y)²+(x+y)(x-y)]÷2x,其中x=3,y=1
先化简再求值 [(x-y)²+(x+y)(x-y)]÷2x,其中x=3,y=1

先化简再求值 [(x-y)²+(x+y)(x-y)]÷2x,其中x=3,y=1
[﹙x-y﹚²+﹙x+y﹚﹙x-y﹚]÷2x
=[(x²-2xy+y²)+(x²-y²)]÷2x
=(2x²-2xy)÷2x
=x-y
∵x=3,y=1.5
∴原式=3-1.5=1.5