Mister Exam

tg(t)<1 inequation

A inequation with variable

The solution

You have entered [src]
tan(t) < 1
$$\tan{\left(t \right)} < 1$$
tan(t) < 1
Detail solution
Given the inequality:
$$\tan{\left(t \right)} < 1$$
To solve this inequality, we must first solve the corresponding equation:
$$\tan{\left(t \right)} = 1$$
Solve:
Given the equation
$$\tan{\left(t \right)} = 1$$
- this is the simplest trigonometric equation
This equation is transformed to
$$t = \pi n + \operatorname{atan}{\left(1 \right)}$$
Or
$$t = \pi n + \frac{\pi}{4}$$
, where n - is a integer
$$t_{1} = \pi n + \frac{\pi}{4}$$
$$t_{1} = \pi n + \frac{\pi}{4}$$
This roots
$$t_{1} = \pi n + \frac{\pi}{4}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$t_{0} < t_{1}$$
For example, let's take the point
$$t_{0} = t_{1} - \frac{1}{10}$$
=
$$\left(\pi n + \frac{\pi}{4}\right) + - \frac{1}{10}$$
=
$$\pi n - \frac{1}{10} + \frac{\pi}{4}$$
substitute to the expression
$$\tan{\left(t \right)} < 1$$
$$\tan{\left(\pi n - \frac{1}{10} + \frac{\pi}{4} \right)} < 1$$
   /  1    pi       \    
tan|- -- + -- + pi*n| < 1
   \  10   4        /    

the solution of our inequality is:
$$t < \pi n + \frac{\pi}{4}$$
 _____          
      \    
-------ο-------
       t1
Solving inequality on a graph
Rapid solution [src]
  /   /            pi\     /         pi    \\
Or|And|0 <= t, t < --|, And|t <= pi, -- < t||
  \   \            4 /     \         2     //
$$\left(0 \leq t \wedge t < \frac{\pi}{4}\right) \vee \left(t \leq \pi \wedge \frac{\pi}{2} < t\right)$$
((0 <= t)∧(t < pi/4))∨((t <= pi)∧(pi/2 < t))
Rapid solution 2 [src]
    pi     pi     
[0, --) U (--, pi]
    4      2      
$$t\ in\ \left[0, \frac{\pi}{4}\right) \cup \left(\frac{\pi}{2}, \pi\right]$$
t in Union(Interval.Ropen(0, pi/4), Interval.Lopen(pi/2, pi))