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cot(x)>(sqrt(3))*1/3 inequation

A inequation with variable

The solution

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cot(x) > -----
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$$\cot{\left(x \right)} > \frac{\sqrt{3}}{3}$$
cot(x) > sqrt(3)/3
Detail solution
Given the inequality:
$$\cot{\left(x \right)} > \frac{\sqrt{3}}{3}$$
To solve this inequality, we must first solve the corresponding equation:
$$\cot{\left(x \right)} = \frac{\sqrt{3}}{3}$$
Solve:
Given the equation
$$\cot{\left(x \right)} = \frac{\sqrt{3}}{3}$$
transform
$$\cot{\left(x \right)} - 1 - \frac{\sqrt{3}}{3} = 0$$
$$\cot{\left(x \right)} - 1 - \frac{\sqrt{3}}{3} = 0$$
Do replacement
$$w = \cot{\left(x \right)}$$
Expand brackets in the left part
-1 + w - sqrt3/3 = 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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{\pi}{3}$$
=
$$- \frac{1}{10} + \frac{\pi}{3}$$
substitute to the expression
$$\cot{\left(x \right)} > \frac{\sqrt{3}}{3}$$
$$\cot{\left(- \frac{1}{10} + \frac{\pi}{3} \right)} > \frac{\sqrt{3}}{3}$$
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   /1    pi\   \/ 3 
tan|-- + --| > -----
   \10   6 /     3  
               

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