Nếu \({{\left( \sqrt{3}-\sqrt{2} \right)}^{x}}>\sqrt{3}+\sqrt{2}\)thì

* Hướng dẫn giải

Vì \(\left( \sqrt{3}-\sqrt{2} \right).\left( \sqrt{3}+\sqrt{2} \right)=1\)\(\Leftrightarrow \left( \sqrt{3}+\sqrt{2} \right)=\frac{1}{\left( \sqrt{3}+\sqrt{2} \right)}\)nên

\({{\left( \sqrt{3}-\sqrt{2} \right)}^{x}}>\sqrt{3}+\sqrt{2}\)\(\Leftrightarrow {{\left( \sqrt{3}-\sqrt{2} \right)}^{x}}>\frac{1}{\sqrt{3}-\sqrt{2}}\)\(\Leftrightarrow {{\left( \sqrt{3}-\sqrt{2} \right)}^{x}}>{{\left( \sqrt{3}-\sqrt{2} \right)}^{-1}}\).

Mặt khác \(0<\sqrt{3}-\sqrt{2}<1\) \(\Rightarrow \)\(x<-1\). Vậy đáp án A là chính xác.