Find domain of the above given function with explanation

The domain of √f(x) is such that f(x)=>0. So for this function . Solve three inequality and take intersection. 1.) 1-(√(1-(√1-x²)))=>0 then you get x€[-1,1]. Then 2.) 1-(√1-x²)=>0. Then you get x€[0,1]. Then 3.) √(1-x²)=>0 then x€[-1,1]. Then when u take intersection of these u get x€[0,1]. Hope it clears. If still u have doubts then please clarify. If u like answer then please approve the answer.