[tex]Mai\ intai\ trebuie\ sa\ punem\ conditiile\ de\ existenta\ ale\ radicalului:\\
1-x^2\geq0\\
x^2\leq 1\Rightarrow x\in[-1,1] (1) \\
Rezolvam\ ecuatia:\\
-1\leq x-\sqrt{1-x^2}\\
\sqrt{1-x^2}\leq x+1 |^2\\
1-x^2\leq x^2+2x+1\\
2x^2+2x\geq 0\\
x(x+1)\geq 0\Rightarrow x\in (-\infty,-1]\cup[0,+\infty)(2)\\
Daca\ intersectam(1)\ cu\ (2)\Rightarrow x\in[0,1]\\
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