# Trigonometry! #31

Geometry Level 4

Find the value of $\cos(2\cos^{-1}x + \sin^{-1}x)$ at $$x=\frac {1}{5}$$, where $$0≤\cos^{-1}x≤\pi$$ and $$\frac {-\pi}{2} ≤ \sin^{-1}x ≤ \frac {\pi}{2}$$.

If your answer is in the form of $$-\frac {a\sqrt{b}}{c}$$, where $$b$$ is a square free integer, enter the value of $$a+b+c$$.

This problem is part of the set Trigonometry.

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