化简求值 [(x-y^2)+(x+y)(x-y)]÷2x.
问题描述：
化简求值 [(x-y^2)+(x+y)(x-y)]÷2x.
[(x-y^2)+(x+y)(x-y)]÷2x.
化简求值 x=3 y=1.5
答
[(x-y^2)+(x+y)(x-y)]÷2x=[x-y²+x²-y²]÷2x=[x²+x-2y²]/2x=(x+1)/2-y²/x ,将 x=3 y=1.5代人上式,原式＝(3+1)/2-1.5²/3＝2-2.25/3＝1.25.