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sinx>=0.5

sinx>=0.5 inequation

A inequation with variable

The solution

You have entered [src]
sin(x) >= 1/2
$$\sin{\left(x \right)} \geq \frac{1}{2}$$
sin(x) >= 1/2
Detail solution
Given the inequality:
$$\sin{\left(x \right)} \geq \frac{1}{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\sin{\left(x \right)} = \frac{1}{2}$$
Solve:
Given the equation
$$\sin{\left(x \right)} = \frac{1}{2}$$
- this is the simplest trigonometric equation
This equation is transformed to
$$x = 2 \pi n + \operatorname{asin}{\left(\frac{1}{2} \right)}$$
$$x = 2 \pi n - \operatorname{asin}{\left(\frac{1}{2} \right)} + \pi$$
Or
$$x = 2 \pi n + \frac{\pi}{6}$$
$$x = 2 \pi n + \frac{5 \pi}{6}$$
, where n - is a integer
$$x_{1} = 2 \pi n + \frac{\pi}{6}$$
$$x_{2} = 2 \pi n + \frac{5 \pi}{6}$$
$$x_{1} = 2 \pi n + \frac{\pi}{6}$$
$$x_{2} = 2 \pi n + \frac{5 \pi}{6}$$
This roots
$$x_{1} = 2 \pi n + \frac{\pi}{6}$$
$$x_{2} = 2 \pi n + \frac{5 \pi}{6}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(2 \pi n + \frac{\pi}{6}\right) - \frac{1}{10}$$
=
$$2 \pi n - \frac{1}{10} + \frac{\pi}{6}$$
substitute to the expression
$$\sin{\left(x \right)} \geq \frac{1}{2}$$
$$\sin{\left(2 \pi n - \frac{1}{10} + \frac{\pi}{6} \right)} \geq \frac{1}{2}$$
   /1    pi\       
cos|-- + --| >= 1/2
   \10   3 /       

but
   /1    pi\      
cos|-- + --| < 1/2
   \10   3 /      

Then
$$x \leq 2 \pi n + \frac{\pi}{6}$$
no execute
one of the solutions of our inequality is:
$$x \geq 2 \pi n + \frac{\pi}{6} \wedge x \leq 2 \pi n + \frac{5 \pi}{6}$$
         _____  
        /     \  
-------•-------•-------
       x_1      x_2
Solving inequality on a graph
Rapid solution [src]
   /pi            5*pi\
And|-- <= x, x <= ----|
   \6              6  /
$$\frac{\pi}{6} \leq x \wedge x \leq \frac{5 \pi}{6}$$
(pi/6 <= x)∧(x <= 5*pi/6)
Rapid solution 2 [src]
 pi  5*pi 
[--, ----]
 6    6   
$$x\ in\ \left[\frac{\pi}{6}, \frac{5 \pi}{6}\right]$$
x in Interval(pi/6, 5*pi/6)
The graph
sinx>=0.5 inequation