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cot(x)>-sqrt(3)/3 inequation

A inequation with variable

The solution

You have entered [src]
            ___ 
         -\/ 3  
cot(x) > -------
            3   
$$\cot{\left(x \right)} > \frac{\left(-1\right) \sqrt{3}}{3}$$
cot(x) > (-sqrt(3))/3
Detail solution
Given the inequality:
$$\cot{\left(x \right)} > \frac{\left(-1\right) \sqrt{3}}{3}$$
To solve this inequality, we must first solve the corresponding equation:
$$\cot{\left(x \right)} = \frac{\left(-1\right) \sqrt{3}}{3}$$
Solve:
Given the equation
$$\cot{\left(x \right)} = \frac{\left(-1\right) \sqrt{3}}{3}$$
transform
$$\cot{\left(x \right)} - 1 + \frac{\sqrt{3}}{3} = 0$$
$$\cot{\left(x \right)} - 1 - \frac{\left(-1\right) \sqrt{3}}{3} = 0$$
Do replacement
$$w = \cot{\left(x \right)}$$
Expand brackets in the left part
-1 + w - -sqrt+3)/3 = 0

Move free summands (without w)
from left part to right part, we given:
$$w + \frac{\sqrt{3}}{3} = 1$$
Divide both parts of the equation by (w + sqrt(3)/3)/w
w = 1 / ((w + sqrt(3)/3)/w)

We get the answer: w = 1 - sqrt(3)/3
do backward replacement
$$\cot{\left(x \right)} = w$$
substitute w:
$$x_{1} = - \frac{\pi}{3}$$
$$x_{1} = - \frac{\pi}{3}$$
This roots
$$x_{1} = - \frac{\pi}{3}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{\pi}{3} - \frac{1}{10}$$
=
$$- \frac{\pi}{3} - \frac{1}{10}$$
substitute to the expression
$$\cot{\left(x \right)} > \frac{\left(-1\right) \sqrt{3}}{3}$$
$$\cot{\left(- \frac{\pi}{3} - \frac{1}{10} \right)} > \frac{\left(-1\right) \sqrt{3}}{3}$$
                   ___ 
    /1    pi\   -\/ 3  
-cot|-- + --| > -------
    \10   3 /      3   
                

the solution of our inequality is:
$$x < - \frac{\pi}{3}$$
 _____          
      \    
-------ο-------
       x1
Rapid solution [src]
   /           2*pi\
And|0 < x, x < ----|
   \            3  /
$$0 < x \wedge x < \frac{2 \pi}{3}$$
(0 < x)∧(x < 2*pi/3)
Rapid solution 2 [src]
    2*pi 
(0, ----)
     3   
$$x\ in\ \left(0, \frac{2 \pi}{3}\right)$$
x in Interval.open(0, 2*pi/3)