question_answer

If \[{{(5+2\sqrt{6})}^{{{x}^{2}}-3}}+{{(5-2\sqrt{6})}^{{{x}^{2}}-3}}=10,\] then x is equal to:

A)  \[2,2\]                          

B)  \[\sqrt{2,}-\sqrt{2}\]

C)  \[2,+\sqrt{2}\]             

D)  \[2,-2,\sqrt{2},-\sqrt{2}\]

E)  None of these