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(4x-2x^2-4)/(x^2+2x+1)<=0 inequation

A inequation with variable

The solution

You have entered [src]
         2         
4*x - 2*x  - 4     
-------------- <= 0
  2                
 x  + 2*x + 1      
$$\frac{\left(- 2 x^{2} + 4 x\right) - 4}{\left(x^{2} + 2 x\right) + 1} \leq 0$$
(-2*x^2 + 4*x - 4)/(x^2 + 2*x + 1) <= 0
Detail solution
Given the inequality:
$$\frac{\left(- 2 x^{2} + 4 x\right) - 4}{\left(x^{2} + 2 x\right) + 1} \leq 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\frac{\left(- 2 x^{2} + 4 x\right) - 4}{\left(x^{2} + 2 x\right) + 1} = 0$$
Solve:
Given the equation:
$$\frac{\left(- 2 x^{2} + 4 x\right) - 4}{\left(x^{2} + 2 x\right) + 1} = 0$$
Multiply the equation sides by the denominators:
1 + x^2 + 2*x
we get:
$$\frac{\left(\left(- 2 x^{2} + 4 x\right) - 4\right) \left(x^{2} + 2 x + 1\right)}{\left(x^{2} + 2 x\right) + 1} = 0$$
$$- 2 x^{2} + 4 x - 4 = 0$$
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
$$a = -2$$
$$b = 4$$
$$c = -4$$
, then
D = b^2 - 4 * a * c = 

(4)^2 - 4 * (-2) * (-4) = -16

Because D<0, then the equation
has no real roots,
but complex roots is exists.
x1 = (-b + sqrt(D)) / (2*a)

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

or
$$x_{1} = 1 - i$$
$$x_{2} = 1 + i$$
$$x_{1} = 1 - i$$
$$x_{2} = 1 + i$$
Exclude the complex solutions:
This equation has no roots,
this inequality is executed for any x value or has no solutions
check it
subtitute random point x, for example
x0 = 0

$$\frac{-4 + \left(0 \cdot 4 - 2 \cdot 0^{2}\right)}{\left(0^{2} + 0 \cdot 2\right) + 1} \leq 0$$
-4 <= 0

so the inequality is always executed
Solving inequality on a graph
Rapid solution [src]
And(x > -oo, x < oo, x != -1)
$$x > -\infty \wedge x < \infty \wedge x \neq -1$$
(x > -oo)∧(x < oo)∧(Ne(x, -1))
Rapid solution 2 [src]
(-oo, -1) U (-1, oo)
$$x\ in\ \left(-\infty, -1\right) \cup \left(-1, \infty\right)$$
x in Union(Interval.open(-oo, -1), Interval.open(-1, oo))