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tg(x)>=2 inequation

A inequation with variable

The solution

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tan(x) >= 2
tan(x)2\tan{\left(x \right)} \geq 2
tan(x) >= 2
Detail solution
Given the inequality:
tan(x)2\tan{\left(x \right)} \geq 2
To solve this inequality, we must first solve the corresponding equation:
tan(x)=2\tan{\left(x \right)} = 2
Solve:
Given the equation
tan(x)=2\tan{\left(x \right)} = 2
- this is the simplest trigonometric equation
This equation is transformed to
x=πn+atan(2)x = \pi n + \operatorname{atan}{\left(2 \right)}
Or
x=πn+atan(2)x = \pi n + \operatorname{atan}{\left(2 \right)}
, where n - is a integer
x1=πn+atan(2)x_{1} = \pi n + \operatorname{atan}{\left(2 \right)}
x1=πn+atan(2)x_{1} = \pi n + \operatorname{atan}{\left(2 \right)}
This roots
x1=πn+atan(2)x_{1} = \pi n + \operatorname{atan}{\left(2 \right)}
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
x0x1x_{0} \leq x_{1}
For example, let's take the point
x0=x1110x_{0} = x_{1} - \frac{1}{10}
=
(πn+atan(2))+110\left(\pi n + \operatorname{atan}{\left(2 \right)}\right) + - \frac{1}{10}
=
πn110+atan(2)\pi n - \frac{1}{10} + \operatorname{atan}{\left(2 \right)}
substitute to the expression
tan(x)2\tan{\left(x \right)} \geq 2
tan(πn110+atan(2))2\tan{\left(\pi n - \frac{1}{10} + \operatorname{atan}{\left(2 \right)} \right)} \geq 2
tan(-1/10 + pi*n + atan(2)) >= 2

but
tan(-1/10 + pi*n + atan(2)) < 2

Then
xπn+atan(2)x \leq \pi n + \operatorname{atan}{\left(2 \right)}
no execute
the solution of our inequality is:
xπn+atan(2)x \geq \pi n + \operatorname{atan}{\left(2 \right)}
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       x1
Solving inequality on a graph
0-80-60-40-2020406080-500000500000
Rapid solution 2 [src]
          pi 
[atan(2), --)
          2  
x in [atan(2),π2)x\ in\ \left[\operatorname{atan}{\left(2 \right)}, \frac{\pi}{2}\right)
x in Interval.Ropen(atan(2), pi/2)
Rapid solution [src]
   /                  pi\
And|atan(2) <= x, x < --|
   \                  2 /
atan(2)xx<π2\operatorname{atan}{\left(2 \right)} \leq x \wedge x < \frac{\pi}{2}
(atan(2) <= x)∧(x < pi/2)