ĐK:\(-3\le x\le3.\)
\(\Leftrightarrow\sqrt{9-x^2}\ge-\left(\sqrt{3+x}+\sqrt{3-x}\right)+3+2\sqrt{3}\)
VP\(\le-2\sqrt{9-x^2}+3+2\sqrt{3}\)(BĐT Cô-si)\(\le\sqrt{9-x^2}\)
\(\Leftrightarrow3\sqrt{9-x^2}\ge3+2\sqrt{3}\)
\(\Leftrightarrow-\sqrt{\dfrac{20-4\sqrt{3}}{3}}\le x\le\sqrt{\dfrac{20-4\sqrt{3}}{3}}\left(TM\right)\)