# Simplify the radical

I need to simplify this radical, $\sqrt{2+e^{8t}+e^{-8t}}$ How is this done? I do not know where to go from here to simplify this further.

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## 1 Answer

Hint: Use the identity $(x+x^{-1})^2 = x^2+2+x^{-2}$ for $x = e^{4t}$.

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