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2,8x^2+6,22x-6,5<4,5-1,78x-0,2x^2

2,8x^2+6,22x-6,5<4,5-1,78x-0,2x^2 inequation

A inequation with variable

The solution

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    2                              2
14*x    311*x          9   89*x   x 
----- + ----- - 13/2 < - - ---- - --
  5       50           2    50    5 
$$\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2} < - \frac{x^{2}}{5} - \frac{89 x}{50} + \frac{9}{2}$$
14*x^2/5 + 311*x/50 - 1*13/2 < -x^2/5 - 89*x/50 + 9/2
Detail solution
Given the inequality:
$$\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2} < - \frac{x^{2}}{5} - \frac{89 x}{50} + \frac{9}{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2} = - \frac{x^{2}}{5} - \frac{89 x}{50} + \frac{9}{2}$$
Solve:
Move right part of the equation to
left part with negative sign.

The equation is transformed from
$$\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2} = - \frac{x^{2}}{5} - \frac{89 x}{50} + \frac{9}{2}$$
to
$$\left(\frac{x^{2}}{5} + \frac{89 x}{50} - \frac{9}{2}\right) + \left(\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2}\right) = 0$$
Expand the expression in the equation
$$\left(\frac{x^{2}}{5} + \frac{89 x}{50} - \frac{9}{2}\right) + \left(\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2}\right) = 0$$
We get the quadratic equation
$$3 x^{2} + 8 x - 11 = 0$$
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
$$a = 3$$
$$b = 8$$
$$c = -11$$
, then
D = b^2 - 4 * a * c = 

(8)^2 - 4 * (3) * (-11) = 196

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

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

or
$$x_{1} = 1$$
Simplify
$$x_{2} = - \frac{11}{3}$$
Simplify
$$x_{1} = 1$$
$$x_{2} = - \frac{11}{3}$$
$$x_{1} = 1$$
$$x_{2} = - \frac{11}{3}$$
This roots
$$x_{2} = - \frac{11}{3}$$
$$x_{1} = 1$$
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
$$x_{0} = x_{2} - \frac{1}{10}$$
=
$$- \frac{11}{3} - \frac{1}{10}$$
=
$$- \frac{113}{30}$$
substitute to the expression
$$\frac{14 x^{2}}{5} + \frac{311 x}{50} - \frac{13}{2} < - \frac{x^{2}}{5} - \frac{89 x}{50} + \frac{9}{2}$$
$$\frac{311}{50} \left(- \frac{113}{30}\right) - \frac{13}{2} + \frac{14 \left(- \frac{113}{30}\right)^{2}}{5} < - \frac{\left(- \frac{113}{30}\right)^{2}}{5} + \frac{9}{2} - \frac{89}{50} \left(- \frac{113}{30}\right)$$
44087   9413
----- < ----
 4500   1125

but
44087   9413
----- > ----
 4500   1125

Then
$$x < - \frac{11}{3}$$
no execute
one of the solutions of our inequality is:
$$x > - \frac{11}{3} \wedge x < 1$$
         _____  
        /     \  
-------ο-------ο-------
       x_2      x_1
Solving inequality on a graph
Rapid solution [src]
And(-11/3 < x, x < 1)
$$- \frac{11}{3} < x \wedge x < 1$$
(-11/3 < x)∧(x < 1)
Rapid solution 2 [src]
(-11/3, 1)
$$x\ in\ \left(- \frac{11}{3}, 1\right)$$
x in Interval.open(-11/3, 1)
The graph
2,8x^2+6,22x-6,5<4,5-1,78x-0,2x^2 inequation