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x^2+4*x+2=0

x^2+4*x+2=0 equation

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Numerical solution:

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The solution

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 2              
x  + 4*x + 2 = 0
$$\left(x^{2} + 4 x\right) + 2 = 0$$
Detail solution
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
$$a = 1$$
$$b = 4$$
$$c = 2$$
, then
D = b^2 - 4 * a * c = 

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

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

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

or
$$x_{1} = -2 + \sqrt{2}$$
$$x_{2} = -2 - \sqrt{2}$$
Vieta's Theorem
it is reduced quadratic equation
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = 4$$
$$q = \frac{c}{a}$$
$$q = 2$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = -4$$
$$x_{1} x_{2} = 2$$
The graph
Sum and product of roots [src]
sum
       ___          ___
-2 - \/ 2  + -2 + \/ 2 
$$\left(-2 - \sqrt{2}\right) + \left(-2 + \sqrt{2}\right)$$
=
-4
$$-4$$
product
/       ___\ /       ___\
\-2 - \/ 2 /*\-2 + \/ 2 /
$$\left(-2 - \sqrt{2}\right) \left(-2 + \sqrt{2}\right)$$
=
2
$$2$$
2
Rapid solution [src]
            ___
x1 = -2 - \/ 2 
$$x_{1} = -2 - \sqrt{2}$$
            ___
x2 = -2 + \/ 2 
$$x_{2} = -2 + \sqrt{2}$$
x2 = -2 + sqrt(2)
Numerical answer [src]
x1 = -3.41421356237309
x2 = -0.585786437626905
x2 = -0.585786437626905
The graph
x^2+4*x+2=0 equation