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√3*(-2)cosx≥0 inequation

A inequation with variable

The solution

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\/ 3 *(-2)*cos(x) >= 0
$$\left(-2\right) \sqrt{3} \cos{\left(x \right)} \geq 0$$
((-2)*sqrt(3))*cos(x) >= 0
Detail solution
Given the inequality:
$$\left(-2\right) \sqrt{3} \cos{\left(x \right)} \geq 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\left(-2\right) \sqrt{3} \cos{\left(x \right)} = 0$$
Solve:
Given the equation
$$\left(-2\right) \sqrt{3} \cos{\left(x \right)} = 0$$
- this is the simplest trigonometric equation
with the change of sign in 0

We get:
$$\left(-2\right) \sqrt{3} \cos{\left(x \right)} = 0$$
Divide both parts of the equation by -2*sqrt(3)

The equation is transformed to
$$\cos{\left(x \right)} = 0$$
This equation is transformed to
$$x = \pi n + \operatorname{acos}{\left(0 \right)}$$
$$x = \pi n - \pi + \operatorname{acos}{\left(0 \right)}$$
Or
$$x = \pi n + \frac{\pi}{2}$$
$$x = \pi n - \frac{\pi}{2}$$
, where n - is a integer
$$x_{1} = \pi n + \frac{\pi}{2}$$
$$x_{2} = \pi n - \frac{\pi}{2}$$
$$x_{1} = \pi n + \frac{\pi}{2}$$
$$x_{2} = \pi n - \frac{\pi}{2}$$
This roots
$$x_{1} = \pi n + \frac{\pi}{2}$$
$$x_{2} = \pi n - \frac{\pi}{2}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(\pi n + \frac{\pi}{2}\right) + - \frac{1}{10}$$
=
$$\pi n - \frac{1}{10} + \frac{\pi}{2}$$
substitute to the expression
$$\left(-2\right) \sqrt{3} \cos{\left(x \right)} \geq 0$$
$$\left(-2\right) \sqrt{3} \cos{\left(\pi n - \frac{1}{10} + \frac{\pi}{2} \right)} \geq 0$$
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2*\/ 3 *sin(-1/10 + pi*n) >= 0
     

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

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