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x^2-4x+6<0 inequation

A inequation with variable

The solution

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x  - 4*x + 6 < 0
$$\left(x^{2} - 4 x\right) + 6 < 0$$
x^2 - 4*x + 6 < 0
Detail solution
Given the inequality:
$$\left(x^{2} - 4 x\right) + 6 < 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\left(x^{2} - 4 x\right) + 6 = 0$$
Solve:
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
$$a = 1$$
$$b = -4$$
$$c = 6$$
, then
D = b^2 - 4 * a * c = 

(-4)^2 - 4 * (1) * (6) = -8

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
$$x_{1} = 2 + \sqrt{2} i$$
$$x_{2} = 2 - \sqrt{2} i$$
$$x_{1} = 2 + \sqrt{2} i$$
$$x_{2} = 2 - \sqrt{2} i$$
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

$$\left(0^{2} - 0 \cdot 4\right) + 6 < 0$$
6 < 0

but
6 > 0

so the inequality has no solutions
Solving inequality on a graph
Rapid solution
This inequality has no solutions