# Celebrating year 2016!

Algebra Level 5

$$\large f_{n+1}(x)=\sqrt{7-\sqrt{7+f_{n}(x)}}$$ and $$\large f_{1}(x)=\sqrt{7-\sqrt{7+x}}$$

A sequence of functions is defined by the previous recursive definition. Which one of the options is true for the following equation? $\large f_{2016}(x)=x$

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