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(|2*x-4|)<4 inequation

A inequation with variable

The solution

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|2*x - 4| < 4
$$\left|{2 x - 4}\right| < 4$$
|2*x - 4| < 4
Detail solution
Given the inequality:
$$\left|{2 x - 4}\right| < 4$$
To solve this inequality, we must first solve the corresponding equation:
$$\left|{2 x - 4}\right| = 4$$
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
$$\left(2 x - 4\right) - 4 = 0$$
after simplifying we get
$$2 x - 8 = 0$$
the solution in this interval:
$$x_{1} = 4$$

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


$$x_{1} = 4$$
$$x_{2} = 0$$
$$x_{1} = 4$$
$$x_{2} = 0$$
This roots
$$x_{2} = 0$$
$$x_{1} = 4$$
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
$$x_{0} = x_{2} - \frac{1}{10}$$
=
$$- \frac{1}{10}$$
=
$$- \frac{1}{10}$$
substitute to the expression
$$\left|{2 x - 4}\right| < 4$$
$$\left|{-4 + \frac{\left(-1\right) 2}{10}}\right| < 4$$
21/5 < 4

but
21/5 > 4

Then
$$x < 0$$
no execute
one of the solutions of our inequality is:
$$x > 0 \wedge x < 4$$
         _____  
        /     \  
-------ο-------ο-------
       x2      x1
Solving inequality on a graph
Rapid solution [src]
And(0 < x, x < 4)
$$0 < x \wedge x < 4$$
(0 < x)∧(x < 4)
Rapid solution 2 [src]
(0, 4)
$$x\ in\ \left(0, 4\right)$$
x in Interval.open(0, 4)