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

A inequation with variable

The solution

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         \/ 3 
cot(x) > -----
           3  
cot(x)>33\cot{\left(x \right)} > \frac{\sqrt{3}}{3}
cot(x) > sqrt(3)/3
Detail solution
Given the inequality:
cot(x)>33\cot{\left(x \right)} > \frac{\sqrt{3}}{3}
To solve this inequality, we must first solve the corresponding equation:
cot(x)=33\cot{\left(x \right)} = \frac{\sqrt{3}}{3}
Solve:
Given the equation
cot(x)=33\cot{\left(x \right)} = \frac{\sqrt{3}}{3}
transform
cot(x)133=0\cot{\left(x \right)} - 1 - \frac{\sqrt{3}}{3} = 0
cot(x)133=0\cot{\left(x \right)} - 1 - \frac{\sqrt{3}}{3} = 0
Do replacement
w=cot(x)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:
w33=1w - \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(x)=w\cot{\left(x \right)} = w
substitute w:
x1=π3x_{1} = \frac{\pi}{3}
x1=π3x_{1} = \frac{\pi}{3}
This roots
x1=π3x_{1} = \frac{\pi}{3}
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
x0<x1x_{0} < x_{1}
For example, let's take the point
x0=x1110x_{0} = x_{1} - \frac{1}{10}
=
110+π3- \frac{1}{10} + \frac{\pi}{3}
=
110+π3- \frac{1}{10} + \frac{\pi}{3}
substitute to the expression
cot(x)>33\cot{\left(x \right)} > \frac{\sqrt{3}}{3}
cot(110+π3)>33\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<π3x < \frac{\pi}{3}
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       x1
Rapid solution 2 [src]
    pi 
(0, --)
    3  
x in (0,π3)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<xx<π30 < x \wedge x < \frac{\pi}{3}
(0 < x)∧(x < pi/3)