Mister Exam

x(6x-5)>0 inequation

A inequation with variable

The solution

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x*(6*x - 5) > 0
$$x \left(6 x - 5\right) > 0$$
x*(6*x - 5) > 0
Detail solution
Given the inequality:
$$x \left(6 x - 5\right) > 0$$
To solve this inequality, we must first solve the corresponding equation:
$$x \left(6 x - 5\right) = 0$$
Solve:
Expand the expression in the equation
$$x \left(6 x - 5\right) = 0$$
We get the quadratic equation
$$6 x^{2} - 5 x = 0$$
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
$$a = 6$$
$$b = -5$$
$$c = 0$$
, then
D = b^2 - 4 * a * c = 

(-5)^2 - 4 * (6) * (0) = 25

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

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

or
$$x_{1} = \frac{5}{6}$$
$$x_{2} = 0$$
$$x_{1} = \frac{5}{6}$$
$$x_{2} = 0$$
$$x_{1} = \frac{5}{6}$$
$$x_{2} = 0$$
This roots
$$x_{2} = 0$$
$$x_{1} = \frac{5}{6}$$
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
$$x \left(6 x - 5\right) > 0$$
$$\frac{\left(-1\right) \left(-5 + \frac{\left(-1\right) 6}{10}\right)}{10} > 0$$
14    
-- > 0
25    

one of the solutions of our inequality is:
$$x < 0$$
 _____           _____          
      \         /
-------ο-------ο-------
       x2      x1

Other solutions will get with the changeover to the next point
etc.
The answer:
$$x < 0$$
$$x > \frac{5}{6}$$
Solving inequality on a graph
Rapid solution [src]
Or(And(-oo < x, x < 0), And(5/6 < x, x < oo))
$$\left(-\infty < x \wedge x < 0\right) \vee \left(\frac{5}{6} < x \wedge x < \infty\right)$$
((-oo < x)∧(x < 0))∨((5/6 < x)∧(x < oo))
Rapid solution 2 [src]
(-oo, 0) U (5/6, oo)
$$x\ in\ \left(-\infty, 0\right) \cup \left(\frac{5}{6}, \infty\right)$$
x in Union(Interval.open(-oo, 0), Interval.open(5/6, oo))