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x+1/2*x-1<0 inequation

A inequation with variable

The solution

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    x        
x + - - 1 < 0
    2        
$$\left(\frac{x}{2} + x\right) - 1 < 0$$
x/2 + x - 1 < 0
Detail solution
Given the inequality:
$$\left(\frac{x}{2} + x\right) - 1 < 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\left(\frac{x}{2} + x\right) - 1 = 0$$
Solve:
Given the linear equation:
x+1/2*x-1 = 0

Looking for similar summands in the left part:
-1 + 3*x/2 = 0

Move free summands (without x)
from left part to right part, we given:
$$\frac{3 x}{2} = 1$$
Divide both parts of the equation by 3/2
x = 1 / (3/2)

$$x_{1} = \frac{2}{3}$$
$$x_{1} = \frac{2}{3}$$
This roots
$$x_{1} = \frac{2}{3}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{2}{3}$$
=
$$\frac{17}{30}$$
substitute to the expression
$$\left(\frac{x}{2} + x\right) - 1 < 0$$
$$-1 + \left(\frac{17}{2 \cdot 30} + \frac{17}{30}\right) < 0$$
-3/20 < 0

the solution of our inequality is:
$$x < \frac{2}{3}$$
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Solving inequality on a graph
Rapid solution 2 [src]
(-oo, 2/3)
$$x\ in\ \left(-\infty, \frac{2}{3}\right)$$
x in Interval.open(-oo, 2/3)
Rapid solution [src]
And(-oo < x, x < 2/3)
$$-\infty < x \wedge x < \frac{2}{3}$$
(-oo < x)∧(x < 2/3)