x,y两数和的相反数乘以x,y两数和的绝对值
问题描述:
x,y两数和的相反数乘以x,y两数和的绝对值
答
-(x+y)*|x+y|
若x+y>0,则-(x+y)*|x+y|=-(x+y)^2
若x+y