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cosx/3<√3/2 inequation

A inequation with variable

The solution

You have entered [src]
           ___
cos(x)   \/ 3 
------ < -----
  3        2  
$$\frac{\cos{\left(x \right)}}{3} < \frac{\sqrt{3}}{2}$$
cos(x)/3 < sqrt(3)/2
Detail solution
Given the inequality:
$$\frac{\cos{\left(x \right)}}{3} < \frac{\sqrt{3}}{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\frac{\cos{\left(x \right)}}{3} = \frac{\sqrt{3}}{2}$$
Solve:
Given the equation
$$\frac{\cos{\left(x \right)}}{3} = \frac{\sqrt{3}}{2}$$
- this is the simplest trigonometric equation
Divide both parts of the equation by 1/3

The equation is transformed to
$$\cos{\left(x \right)} = \frac{3 \sqrt{3}}{2}$$
As right part of the equation
modulo =
True

but cos
can no be more than 1 or less than -1
so the solution of the equation d'not exist.
$$x_{1} = 2 \pi - \operatorname{acos}{\left(\frac{3 \sqrt{3}}{2} \right)}$$
$$x_{2} = \operatorname{acos}{\left(\frac{3 \sqrt{3}}{2} \right)}$$
Exclude the complex solutions:
This equation has no roots,
this inequality is executed for any x value or has no solutions
check it
subtitute random point x, for example
x0 = 0

$$\frac{\cos{\left(0 \right)}}{3} < \frac{\sqrt{3}}{2}$$
        ___
      \/ 3 
1/3 < -----
        2  
      

so the inequality is always executed
Solving inequality on a graph
Rapid solution 2 [src]
(-oo, oo)
$$x\ in\ \left(-\infty, \infty\right)$$
x in Interval(-oo, oo)
Rapid solution [src]
And(-oo < x, x < oo)
$$-\infty < x \wedge x < \infty$$
(-oo < x)∧(x < oo)