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

题目

先化简,再求值：[(x-y)^2+(x+y)(x-y)]÷2x ,其中x=3,y=-2
如题

答案

原式=(x²-2xy+y²+x²-y²)÷2x
=(2x²-2xy)÷2x
=2x²÷2x-2xy÷2x
=x-y
=3-(-2)
=3+2
=5