已知实数x,y满足x+2根号y=2,化简二次根式根号2x+y.

题目

已知实数x,y满足x+2根号y=2,化简二次根式根号2x+y.

答案

x+2根号y=2,
x=2-2根号y
根号2x+y
=根号(4-4根号y+y)
=根号(根号y-2)^2
=|根号y-2|