Given the inequality:
$$\tan{\left(5 x + \frac{\left(-1\right) \pi}{3} \right)} \geq \frac{\left(-1\right) \sqrt{3}}{3}$$
To solve this inequality, we must first solve the corresponding equation:
$$\tan{\left(5 x + \frac{\left(-1\right) \pi}{3} \right)} = \frac{\left(-1\right) \sqrt{3}}{3}$$
Solve:
$$x_{1} = \frac{\pi}{30}$$
$$x_{1} = \frac{\pi}{30}$$
This roots
$$x_{1} = \frac{\pi}{30}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} \leq x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{\pi}{30}$$
=
$$- \frac{1}{10} + \frac{\pi}{30}$$
substitute to the expression
$$\tan{\left(5 x + \frac{\left(-1\right) \pi}{3} \right)} \geq \frac{\left(-1\right) \sqrt{3}}{3}$$
$$\tan{\left(\frac{\left(-1\right) \pi}{3} + 5 \left(- \frac{1}{10} + \frac{\pi}{30}\right) \right)} \geq \frac{\left(-1\right) \sqrt{3}}{3}$$
___
/1 pi\ -\/ 3
-tan|- + --| >= -------
\2 6 / 3
but
___
/1 pi\ -\/ 3
-tan|- + --| < -------
\2 6 / 3
Then
$$x \leq \frac{\pi}{30}$$
no execute
the solution of our inequality is:
$$x \geq \frac{\pi}{30}$$
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