y=根arctan(2-x)的定义域?

y=根arctan(2-x)的定义域?
y=根arctan(2-x)的定义域?

y=根arctan(2-x)的定义域?
提醒：x>0时,arctanx为锐角,x=0,
x

y=√arctan(2-x)
arctan(2-x)≥0
2-x≥0
x≤2

所以定义域是{x|x≤2}