已知实数x,y满足 根号x-2 + (y+1)²=0,则x-y等于
问题描述:
已知实数x,y满足 根号x-2 + (y+1)²=0,则x-y等于
答
√x-2 + (y+1)²=0
则x-2=0 y+1=0
x=2 y=-1 x-y=3