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x^2+8=0

x^2+8=0 equation

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Numerical solution:

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The solution

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 2        
x  + 8 = 0
$$x^{2} + 8 = 0$$
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
$$a = 1$$
$$b = 0$$
$$c = 8$$
, then
D = b^2 - 4 * a * c = 

(0)^2 - 4 * (1) * (8) = -32

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
$$x_{1} = 2 \sqrt{2} i$$
$$x_{2} = - 2 \sqrt{2} i$$
Vieta's Theorem
it is reduced quadratic equation
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = 0$$
$$q = \frac{c}{a}$$
$$q = 8$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 0$$
$$x_{1} x_{2} = 8$$
The graph
Sum and product of roots [src]
sum
        ___         ___
- 2*I*\/ 2  + 2*I*\/ 2 
$$- 2 \sqrt{2} i + 2 \sqrt{2} i$$
=
0
$$0$$
product
       ___       ___
-2*I*\/ 2 *2*I*\/ 2 
$$- 2 \sqrt{2} i 2 \sqrt{2} i$$
=
8
$$8$$
8
Rapid solution [src]
            ___
x1 = -2*I*\/ 2 
$$x_{1} = - 2 \sqrt{2} i$$
           ___
x2 = 2*I*\/ 2 
$$x_{2} = 2 \sqrt{2} i$$
x2 = 2*sqrt(2)*i
Numerical answer [src]
x1 = -2.82842712474619*i
x2 = 2.82842712474619*i
x2 = 2.82842712474619*i
The graph
x^2+8=0 equation