先化简,后求值:【(x-y)²+(x+y)(x-y)】÷2x,其中x=3,y=-1.5
问题描述:
先化简,后求值:【(x-y)²+(x+y)(x-y)】÷2x,其中x=3,y=-1.5
先化简,后求值,要答案和计算过程和公式
答
[(x-y)²+(x+y)(x-y)]÷2x
=(x-y)(x-y+x+y)÷2x
=(x-y)×2x ÷2x
=x-y
=3-(-1.5)
=4.5