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sin<=-(√3)/2 inequation

A inequation with variable

The solution

You have entered [src]
             ___ 
          -\/ 3  
sin(x) <= -------
             2   
$$\sin{\left(x \right)} \leq \frac{\left(-1\right) \sqrt{3}}{2}$$
sin(x) <= (-sqrt(3))/2
Detail solution
Given the inequality:
$$\sin{\left(x \right)} \leq \frac{\left(-1\right) \sqrt{3}}{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\sin{\left(x \right)} = \frac{\left(-1\right) \sqrt{3}}{2}$$
Solve:
Given the equation
$$\sin{\left(x \right)} = \frac{\left(-1\right) \sqrt{3}}{2}$$
- this is the simplest trigonometric equation
This equation is transformed to
$$x = 2 \pi n + \operatorname{asin}{\left(- \frac{\sqrt{3}}{2} \right)}$$
$$x = 2 \pi n - \operatorname{asin}{\left(- \frac{\sqrt{3}}{2} \right)} + \pi$$
Or
$$x = 2 \pi n - \frac{\pi}{3}$$
$$x = 2 \pi n + \frac{4 \pi}{3}$$
, where n - is a integer
$$x_{1} = 2 \pi n - \frac{\pi}{3}$$
$$x_{2} = 2 \pi n + \frac{4 \pi}{3}$$
$$x_{1} = 2 \pi n - \frac{\pi}{3}$$
$$x_{2} = 2 \pi n + \frac{4 \pi}{3}$$
This roots
$$x_{1} = 2 \pi n - \frac{\pi}{3}$$
$$x_{2} = 2 \pi n + \frac{4 \pi}{3}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(2 \pi n - \frac{\pi}{3}\right) + - \frac{1}{10}$$
=
$$2 \pi n - \frac{\pi}{3} - \frac{1}{10}$$
substitute to the expression
$$\sin{\left(x \right)} \leq \frac{\left(-1\right) \sqrt{3}}{2}$$
$$\sin{\left(2 \pi n - \frac{\pi}{3} - \frac{1}{10} \right)} \leq \frac{\left(-1\right) \sqrt{3}}{2}$$
                             ___ 
    /1    pi         \    -\/ 3  
-sin|-- + -- - 2*pi*n| <= -------
    \10   3          /       2   
                          

one of the solutions of our inequality is:
$$x \leq 2 \pi n - \frac{\pi}{3}$$
 _____           _____          
      \         /
-------•-------•-------
       x1      x2

Other solutions will get with the changeover to the next point
etc.
The answer:
$$x \leq 2 \pi n - \frac{\pi}{3}$$
$$x \geq 2 \pi n + \frac{4 \pi}{3}$$
Solving inequality on a graph
Rapid solution [src]
   /4*pi            5*pi\
And|---- <= x, x <= ----|
   \ 3               3  /
$$\frac{4 \pi}{3} \leq x \wedge x \leq \frac{5 \pi}{3}$$
(4*pi/3 <= x)∧(x <= 5*pi/3)
Rapid solution 2 [src]
 4*pi  5*pi 
[----, ----]
  3     3   
$$x\ in\ \left[\frac{4 \pi}{3}, \frac{5 \pi}{3}\right]$$
x in Interval(4*pi/3, 5*pi/3)