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0,5(x-8)*(x+8)>0 inequation

A inequation with variable

The solution

You have entered [src]
x - 8            
-----*(x + 8) > 0
  2              
$$\frac{x - 8}{2} \left(x + 8\right) > 0$$
((x - 8)/2)*(x + 8) > 0
Detail solution
Given the inequality:
$$\frac{x - 8}{2} \left(x + 8\right) > 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\frac{x - 8}{2} \left(x + 8\right) = 0$$
Solve:
Expand the expression in the equation
$$\frac{x - 8}{2} \left(x + 8\right) = 0$$
We get the quadratic equation
$$\frac{x^{2}}{2} - 32 = 0$$
This equation is of the form
a*x^2 + b*x + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = \frac{1}{2}$$
$$b = 0$$
$$c = -32$$
, then
D = b^2 - 4 * a * c = 

(0)^2 - 4 * (1/2) * (-32) = 64

Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)

x2 = (-b - sqrt(D)) / (2*a)

or
$$x_{1} = 8$$
$$x_{2} = -8$$
$$x_{1} = 8$$
$$x_{2} = -8$$
$$x_{1} = 8$$
$$x_{2} = -8$$
This roots
$$x_{2} = -8$$
$$x_{1} = 8$$
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
$$x_{0} = x_{2} - \frac{1}{10}$$
=
$$-8 + - \frac{1}{10}$$
=
$$- \frac{81}{10}$$
substitute to the expression
$$\frac{x - 8}{2} \left(x + 8\right) > 0$$
$$\frac{- \frac{81}{10} - 8}{2} \left(- \frac{81}{10} + 8\right) > 0$$
161    
--- > 0
200    

one of the solutions of our inequality is:
$$x < -8$$
 _____           _____          
      \         /
-------ο-------ο-------
       x2      x1

Other solutions will get with the changeover to the next point
etc.
The answer:
$$x < -8$$
$$x > 8$$
Solving inequality on a graph
Rapid solution 2 [src]
(-oo, -8) U (8, oo)
$$x\ in\ \left(-\infty, -8\right) \cup \left(8, \infty\right)$$
x in Union(Interval.open(-oo, -8), Interval.open(8, oo))
Rapid solution [src]
Or(And(-oo < x, x < -8), And(8 < x, x < oo))
$$\left(-\infty < x \wedge x < -8\right) \vee \left(8 < x \wedge x < \infty\right)$$
((-oo < x)∧(x < -8))∨((8 < x)∧(x < oo))