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tg(x/7-5п/6)<-3

tg(x/7-5п/6)<-3 inequation

A inequation with variable

The solution

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   /x   5*pi\     
tan|- - ----| < -3
   \7    6  /     
$$\tan{\left(\frac{x}{7} - \frac{5 \pi}{6} \right)} < -3$$
tan(x/7 - 5*pi/6) < -3
Detail solution
Given the inequality:
$$\tan{\left(\frac{x}{7} - \frac{5 \pi}{6} \right)} < -3$$
To solve this inequality, we must first solve the corresponding equation:
$$\tan{\left(\frac{x}{7} - \frac{5 \pi}{6} \right)} = -3$$
Solve:
Given the equation
$$\tan{\left(\frac{x}{7} - \frac{5 \pi}{6} \right)} = -3$$
- this is the simplest trigonometric equation
This equation is transformed to
$$\frac{x}{7} + \frac{\pi}{6} = \pi n + \operatorname{atan}{\left(-3 \right)}$$
Or
$$\frac{x}{7} + \frac{\pi}{6} = \pi n - \operatorname{atan}{\left(3 \right)}$$
, where n - is a integer
Move
$$\frac{\pi}{6}$$
to right part of the equation with the opposite sign, in total:
$$\frac{x}{7} = \pi n - \operatorname{atan}{\left(3 \right)} - \frac{\pi}{6}$$
Divide both parts of the equation by
$$\frac{1}{7}$$
get the intermediate answer:
$$x = 7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6}$$
$$x_{1} = 7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6}$$
$$x_{1} = 7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6}$$
This roots
$$x_{1} = 7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6}\right) - \frac{1}{10}$$
=
$$7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6} - \frac{1}{10}$$
substitute to the expression
$$\tan{\left(\frac{x}{7} - \frac{5 \pi}{6} \right)} < -3$$
$$\tan{\left(\frac{7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6} - \frac{1}{10}}{7} - \frac{5 \pi}{6} \right)} < -3$$
-tan(1/70 + atan(3)) < -3

the solution of our inequality is:
$$x < 7 \pi n - 7 \operatorname{atan}{\left(3 \right)} - \frac{7 \pi}{6}$$
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       x_1
Solving inequality on a graph
Rapid solution [src]
   /                    /   ____       ____ \\
   |7*pi                | \/ 10  + 3*\/ 30  ||
And|---- < x, x < 7*atan|-------------------||
   | 3                  |    ____       ____||
   \                    \- \/ 30  + 3*\/ 10 //
$$\frac{7 \pi}{3} < x \wedge x < 7 \operatorname{atan}{\left(\frac{\sqrt{10} + 3 \sqrt{30}}{- \sqrt{30} + 3 \sqrt{10}} \right)}$$
(7*pi/3 < x)∧(x < 7*atan((sqrt(10) + 3*sqrt(30))/(-sqrt(30) + 3*sqrt(10))))
Rapid solution 2 [src]
             /   ____       ____ \ 
 7*pi        | \/ 10  + 3*\/ 30  | 
(----, 7*atan|-------------------|)
  3          |    ____       ____| 
             \- \/ 30  + 3*\/ 10 / 
$$x\ in\ \left(\frac{7 \pi}{3}, 7 \operatorname{atan}{\left(\frac{\sqrt{10} + 3 \sqrt{30}}{- \sqrt{30} + 3 \sqrt{10}} \right)}\right)$$
x in Interval.open(7*pi/3, 7*atan((sqrt(10) + 3*sqrt(30))/(-sqrt(30) + 3*sqrt(10))))
The graph
tg(x/7-5п/6)<-3 inequation