Mister Exam

Other calculators

|2*x-4|<3 inequation

A inequation with variable

The solution

You have entered [src]
|2*x - 4| < 3
$$\left|{2 x - 4}\right| < 3$$
|2*x - 4| < 3
Detail solution
Given the inequality:
$$\left|{2 x - 4}\right| < 3$$
To solve this inequality, we must first solve the corresponding equation:
$$\left|{2 x - 4}\right| = 3$$
Solve:
For every modulo expressions in the equation
allow cases, when this expressions ">=0" or "<0",
solve the resulting equation.

1.
$$2 x - 4 \geq 0$$
or
$$2 \leq x \wedge x < \infty$$
we get the equation
$$\left(2 x - 4\right) - 3 = 0$$
after simplifying we get
$$2 x - 7 = 0$$
the solution in this interval:
$$x_{1} = \frac{7}{2}$$

2.
$$2 x - 4 < 0$$
or
$$-\infty < x \wedge x < 2$$
we get the equation
$$\left(4 - 2 x\right) - 3 = 0$$
after simplifying we get
$$1 - 2 x = 0$$
the solution in this interval:
$$x_{2} = \frac{1}{2}$$


$$x_{1} = \frac{7}{2}$$
$$x_{2} = \frac{1}{2}$$
$$x_{1} = \frac{7}{2}$$
$$x_{2} = \frac{1}{2}$$
This roots
$$x_{2} = \frac{1}{2}$$
$$x_{1} = \frac{7}{2}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{2}$$
For example, let's take the point
$$x_{0} = x_{2} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{1}{2}$$
=
$$\frac{2}{5}$$
substitute to the expression
$$\left|{2 x - 4}\right| < 3$$
$$\left|{-4 + \frac{2 \cdot 2}{5}}\right| < 3$$
16/5 < 3

but
16/5 > 3

Then
$$x < \frac{1}{2}$$
no execute
one of the solutions of our inequality is:
$$x > \frac{1}{2} \wedge x < \frac{7}{2}$$
         _____  
        /     \  
-------ο-------ο-------
       x2      x1
Solving inequality on a graph
Rapid solution [src]
And(1/2 < x, x < 7/2)
$$\frac{1}{2} < x \wedge x < \frac{7}{2}$$
(1/2 < x)∧(x < 7/2)
Rapid solution 2 [src]
(1/2, 7/2)
$$x\ in\ \left(\frac{1}{2}, \frac{7}{2}\right)$$
x in Interval.open(1/2, 7/2)