[(x-y)²+(x+y)(x-y)]/2x
问题描述:
[(x-y)²+(x+y)(x-y)]/2x
x=3,y=-1.5
答
[(x-y)²+(x+y)(x-y)]/2x
=[(x^2-2xy+y^2+x^2-y^2]/2x
=x-y
=4.5