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-2sin(2x)<3^(1/2) inequation

A inequation with variable

The solution

You have entered [src]
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-2*sin(2*x) < \/ 3 
$$- 2 \sin{\left(2 x \right)} < \sqrt{3}$$
-2*sin(2*x) < sqrt(3)
Detail solution
Given the inequality:
$$- 2 \sin{\left(2 x \right)} < \sqrt{3}$$
To solve this inequality, we must first solve the corresponding equation:
$$- 2 \sin{\left(2 x \right)} = \sqrt{3}$$
Solve:
Given the equation
$$- 2 \sin{\left(2 x \right)} = \sqrt{3}$$
- this is the simplest trigonometric equation
Divide both parts of the equation by -2

The equation is transformed to
$$\sin{\left(2 x \right)} = - \frac{\sqrt{3}}{2}$$
This equation is transformed to
$$2 x = 2 \pi n + \operatorname{asin}{\left(- \frac{\sqrt{3}}{2} \right)}$$
$$2 x = 2 \pi n - \operatorname{asin}{\left(- \frac{\sqrt{3}}{2} \right)} + \pi$$
Or
$$2 x = 2 \pi n - \frac{\pi}{3}$$
$$2 x = 2 \pi n + \frac{4 \pi}{3}$$
, where n - is a integer
Divide both parts of the equation by
$$2$$
$$x_{1} = \pi n - \frac{\pi}{6}$$
$$x_{2} = \pi n + \frac{2 \pi}{3}$$
$$x_{1} = \pi n - \frac{\pi}{6}$$
$$x_{2} = \pi n + \frac{2 \pi}{3}$$
This roots
$$x_{1} = \pi n - \frac{\pi}{6}$$
$$x_{2} = \pi n + \frac{2 \pi}{3}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(\pi n - \frac{\pi}{6}\right) + - \frac{1}{10}$$
=
$$\pi n - \frac{\pi}{6} - \frac{1}{10}$$
substitute to the expression
$$- 2 \sin{\left(2 x \right)} < \sqrt{3}$$
$$- 2 \sin{\left(2 \left(\pi n - \frac{\pi}{6} - \frac{1}{10}\right) \right)} < \sqrt{3}$$
     /1   pi         \     ___
2*sin|- + -- - 2*pi*n| < \/ 3 
     \5   3          /   

but
     /1   pi         \     ___
2*sin|- + -- - 2*pi*n| > \/ 3 
     \5   3          /   

Then
$$x < \pi n - \frac{\pi}{6}$$
no execute
one of the solutions of our inequality is:
$$x > \pi n - \frac{\pi}{6} \wedge x < \pi n + \frac{2 \pi}{3}$$
         _____  
        /     \  
-------ο-------ο-------
       x1      x2
Solving inequality on a graph
Rapid solution 2 [src]
    2*pi     5*pi     
[0, ----) U (----, pi]
     3        6       
$$x\ in\ \left[0, \frac{2 \pi}{3}\right) \cup \left(\frac{5 \pi}{6}, \pi\right]$$
x in Union(Interval.Ropen(0, 2*pi/3), Interval.Lopen(5*pi/6, pi))
Rapid solution [src]
  /   /            2*pi\     /         5*pi    \\
Or|And|0 <= x, x < ----|, And|x <= pi, ---- < x||
  \   \             3  /     \          6      //
$$\left(0 \leq x \wedge x < \frac{2 \pi}{3}\right) \vee \left(x \leq \pi \wedge \frac{5 \pi}{6} < x\right)$$
((0 <= x)∧(x < 2*pi/3))∨((x <= pi)∧(5*pi/6 < x))