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z^2+iz+2=0 equation

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Numerical solution:

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The solution

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 2              
z  + I*z + 2 = 0
$$z^{2} + i z + 2 = 0$$
Detail solution
This equation is of the form
a*z^2 + b*z + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$z_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$z_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 1$$
$$b = i$$
$$c = 2$$
, then
D = b^2 - 4 * a * c = 

(i)^2 - 4 * (1) * (2) = -9

Because D<0, then the equation
has no real roots,
but complex roots is exists.
z1 = (-b + sqrt(D)) / (2*a)

z2 = (-b - sqrt(D)) / (2*a)

or
$$z_{1} = i$$
Simplify
$$z_{2} = - 2 i$$
Simplify
Vieta's Theorem
it is reduced quadratic equation
$$p z + z^{2} + q = 0$$
where
$$p = \frac{b}{a}$$
$$p = i$$
$$q = \frac{c}{a}$$
$$q = 2$$
Vieta Formulas
$$z_{1} + z_{2} = - p$$
$$z_{1} z_{2} = q$$
$$z_{1} + z_{2} = - i$$
$$z_{1} z_{2} = 2$$
The graph
Rapid solution [src]
z1 = -2*I
$$z_{1} = - 2 i$$
z2 = I
$$z_{2} = i$$
Sum and product of roots [src]
sum
0 - 2*I + I
$$\left(0 - 2 i\right) + i$$
=
-I
$$- i$$
product
1*-2*I*I
$$i 1 \left(- 2 i\right)$$
=
2
$$2$$
2
Numerical answer [src]
z1 = 1.0*i
z2 = -2.0*i
z2 = -2.0*i