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sin(x/4-3)
A inequation with variable

The solution

               ___
   /x    \   \/ 2 
sin|- - 3| < -----
   \4    /     2  
$$\sin{\left(\frac{x}{4} - 3 \right)} < \frac{\sqrt{2}}{2}$$
sin(x/4 - 3) < sqrt(2)/2
Detail solution
Given the inequality:
$$\sin{\left(\frac{x}{4} - 3 \right)} < \frac{\sqrt{2}}{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\sin{\left(\frac{x}{4} - 3 \right)} = \frac{\sqrt{2}}{2}$$
Solve:
Given the equation
$$\sin{\left(\frac{x}{4} - 3 \right)} = \frac{\sqrt{2}}{2}$$
- this is the simplest trigonometric equation
This equation is transformed to
$$\frac{x}{4} - 3 = 2 \pi n + \operatorname{asin}{\left(\frac{\sqrt{2}}{2} \right)}$$
$$\frac{x}{4} - 3 = 2 \pi n - \operatorname{asin}{\left(\frac{\sqrt{2}}{2} \right)} + \pi$$
Or
$$\frac{x}{4} - 3 = 2 \pi n + \frac{\pi}{4}$$
$$\frac{x}{4} - 3 = 2 \pi n + \frac{3 \pi}{4}$$
, where n - is a integer
Move
$$-3$$
to right part of the equation
with the opposite sign, in total:
$$\frac{x}{4} = 2 \pi n + \frac{\pi}{4} + 3$$
$$\frac{x}{4} = 2 \pi n + \frac{3 \pi}{4} + 3$$
Divide both parts of the equation by
$$\frac{1}{4}$$
$$x_{1} = 8 \pi n + \pi + 12$$
$$x_{2} = 8 \pi n + 3 \pi + 12$$
$$x_{1} = 8 \pi n + \pi + 12$$
$$x_{2} = 8 \pi n + 3 \pi + 12$$
This roots
$$x_{1} = 8 \pi n + \pi + 12$$
$$x_{2} = 8 \pi n + 3 \pi + 12$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$\left(8 \pi n + \pi + 12\right) + - \frac{1}{10}$$
=
$$8 \pi n + \pi + \frac{119}{10}$$
substitute to the expression
$$\sin{\left(\frac{x}{4} - 3 \right)} < \frac{\sqrt{2}}{2}$$
$$\sin{\left(\frac{8 \pi n + \pi + \frac{119}{10}}{4} - 3 \right)} < \frac{\sqrt{2}}{2}$$
                            ___
   /  1    pi         \   \/ 2 
sin|- -- + -- + 2*pi*n| < -----
   \  40   4          /     2  
                          

one of the solutions of our inequality is:
$$x < 8 \pi n + \pi + 12$$
 _____           _____          
      \         /
-------ο-------ο-------
       x1      x2

Other solutions will get with the changeover to the next point
etc.
The answer:
$$x < 8 \pi n + \pi + 12$$
$$x > 8 \pi n + 3 \pi + 12$$
Solving inequality on a graph
Rapid solution [src]
  /   /                    /                  ___        3            ___    4                 ___ /       2     \        \       \     /                   /                  ___        3            ___    4                 ___ /       2     \        \           \\
  |   |                    |-8*tan(3/2) - 2*\/ 2  + 8*tan (3/2) + 2*\/ 2 *tan (3/2)          \/ 2 *\1 + tan (3/2)/        |       |     |                   |-8*tan(3/2) - 2*\/ 2  + 8*tan (3/2) + 2*\/ 2 *tan (3/2)          \/ 2 *\1 + tan (3/2)/        |           ||
Or|And|0 <= x, x < - 8*atan|------------------------------------------------------- + ------------------------------------| + 8*pi|, And|x <= 8*pi, - 8*atan|------------------------------------------------------- - ------------------------------------| + 8*pi < x||
  |   |                    |                       2             4                      ___                  ___    2     |       |     |                   |                       2             4                      ___                  ___    2     |           ||
  \   \                    \             2 - 12*tan (3/2) + 2*tan (3/2)               \/ 2  - 4*tan(3/2) + \/ 2 *tan (3/2)/       /     \                   \             2 - 12*tan (3/2) + 2*tan (3/2)               \/ 2  - 4*tan(3/2) + \/ 2 *tan (3/2)/           //
$$\left(0 \leq x \wedge x < - 8 \operatorname{atan}{\left(\frac{\sqrt{2} \left(1 + \tan^{2}{\left(\frac{3}{2} \right)}\right)}{- 4 \tan{\left(\frac{3}{2} \right)} + \sqrt{2} + \sqrt{2} \tan^{2}{\left(\frac{3}{2} \right)}} + \frac{- 8 \tan{\left(\frac{3}{2} \right)} - 2 \sqrt{2} + 8 \tan^{3}{\left(\frac{3}{2} \right)} + 2 \sqrt{2} \tan^{4}{\left(\frac{3}{2} \right)}}{- 12 \tan^{2}{\left(\frac{3}{2} \right)} + 2 + 2 \tan^{4}{\left(\frac{3}{2} \right)}} \right)} + 8 \pi\right) \vee \left(x \leq 8 \pi \wedge - 8 \operatorname{atan}{\left(- \frac{\sqrt{2} \left(1 + \tan^{2}{\left(\frac{3}{2} \right)}\right)}{- 4 \tan{\left(\frac{3}{2} \right)} + \sqrt{2} + \sqrt{2} \tan^{2}{\left(\frac{3}{2} \right)}} + \frac{- 8 \tan{\left(\frac{3}{2} \right)} - 2 \sqrt{2} + 8 \tan^{3}{\left(\frac{3}{2} \right)} + 2 \sqrt{2} \tan^{4}{\left(\frac{3}{2} \right)}}{- 12 \tan^{2}{\left(\frac{3}{2} \right)} + 2 + 2 \tan^{4}{\left(\frac{3}{2} \right)}} \right)} + 8 \pi < x\right)$$
((0 <= x)∧(x < -8*atan((-8*tan(3/2) - 2*sqrt(2) + 8*tan(3/2)^3 + 2*sqrt(2)*tan(3/2)^4)/(2 - 12*tan(3/2)^2 + 2*tan(3/2)^4) + sqrt(2)*(1 + tan(3/2)^2)/(sqrt(2) - 4*tan(3/2) + sqrt(2)*tan(3/2)^2)) + 8*pi))∨((x <= 8*pi)∧(-8*atan((-8*tan(3/2) - 2*sqrt(2) + 8*tan(3/2)^3 + 2*sqrt(2)*tan(3/2)^4)/(2 - 12*tan(3/2)^2 + 2*tan(3/2)^4) - sqrt(2)*(1 + tan(3/2)^2)/(sqrt(2) - 4*tan(3/2) + sqrt(2)*tan(3/2)^2)) + 8*pi < x))