Mister Exam

Other calculators

tan(2*x)>-sqrt(3) inequation

A inequation with variable

The solution

You have entered [src]
              ___
tan(2*x) > -\/ 3 
$$\tan{\left(2 x \right)} > - \sqrt{3}$$
tan(2*x) > -sqrt(3)
Detail solution
Given the inequality:
$$\tan{\left(2 x \right)} > - \sqrt{3}$$
To solve this inequality, we must first solve the corresponding equation:
$$\tan{\left(2 x \right)} = - \sqrt{3}$$
Solve:
Given the equation
$$\tan{\left(2 x \right)} = - \sqrt{3}$$
- this is the simplest trigonometric equation
This equation is transformed to
$$2 x = \pi n + \operatorname{atan}{\left(- \sqrt{3} \right)}$$
Or
$$2 x = \pi n - \frac{\pi}{3}$$
, where n - is a integer
Divide both parts of the equation by
$$2$$
$$x_{1} = \frac{\pi n}{2} - \frac{\pi}{6}$$
$$x_{1} = \frac{\pi n}{2} - \frac{\pi}{6}$$
This roots
$$x_{1} = \frac{\pi n}{2} - \frac{\pi}{6}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(\frac{\pi n}{2} - \frac{\pi}{6}\right) + - \frac{1}{10}$$
=
$$\frac{\pi n}{2} - \frac{\pi}{6} - \frac{1}{10}$$
substitute to the expression
$$\tan{\left(2 x \right)} > - \sqrt{3}$$
$$\tan{\left(2 \left(\frac{\pi n}{2} - \frac{\pi}{6} - \frac{1}{10}\right) \right)} > - \sqrt{3}$$
    /1   pi       \      ___
-tan|- + -- - pi*n| > -\/ 3 
    \5   3        /   

Then
$$x < \frac{\pi n}{2} - \frac{\pi}{6}$$
no execute
the solution of our inequality is:
$$x > \frac{\pi n}{2} - \frac{\pi}{6}$$
         _____  
        /
-------ο-------
       x1
Solving inequality on a graph
Rapid solution [src]
  /   /            pi\     /     pi  pi    \\
Or|And|0 <= x, x < --|, And|x <= --, -- < x||
  \   \            4 /     \     2   3     //
$$\left(0 \leq x \wedge x < \frac{\pi}{4}\right) \vee \left(x \leq \frac{\pi}{2} \wedge \frac{\pi}{3} < x\right)$$
((0 <= x)∧(x < pi/4))∨((x <= pi/2)∧(pi/3 < x))
Rapid solution 2 [src]
    pi     pi  pi 
[0, --) U (--, --]
    4      3   2  
$$x\ in\ \left[0, \frac{\pi}{4}\right) \cup \left(\frac{\pi}{3}, \frac{\pi}{2}\right]$$
x in Union(Interval.Ropen(0, pi/4), Interval.Lopen(pi/3, pi/2))