# Trigonometry! #72

Geometry Level 4

The solution set of $|4\sin (x) - 1| < \sqrt {5}$ for $$|x|<\pi$$ is

Options:

1. $$\left(-\pi,-\frac {4\pi}{5} \right)\cup\left(-\frac {\pi}{5} , \frac {\pi}{10} \right) \cup \left( \frac {9\pi}{10} , \pi\right)$$

2. $$\left(-\frac {9\pi}{10}, -\frac {\pi}{10}\right) \cup \left(\frac {3\pi}{10} , \frac {7\pi}{10} \right)$$

3. $$\left(-\pi,-\frac {9\pi}{10}\right)\cup\left(-\frac {\pi}{10},\frac{3\pi}{10}\right)\cup\left(\frac{7\pi}{10},\pi\right)$$

4. $$\left(-\frac {7\pi}{10} , \frac {9\pi}{10}\right)$$

Note: Enter the serial number of the correct option.

This problem is part of the set Trigonometry.

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