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-x^2+2*x-3=0

-x^2+2*x-3=0 equation

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Numerical solution:

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The solution

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   2              
- x  + 2*x - 3 = 0
$$\left(- x^{2} + 2 x\right) - 3 = 0$$
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
$$a = -1$$
$$b = 2$$
$$c = -3$$
, then
D = b^2 - 4 * a * c = 

(2)^2 - 4 * (-1) * (-3) = -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
$$x_{1} = 1 - \sqrt{2} i$$
$$x_{2} = 1 + \sqrt{2} i$$
Vieta's Theorem
rewrite the equation
$$\left(- x^{2} + 2 x\right) - 3 = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - 2 x + 3 = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = -2$$
$$q = \frac{c}{a}$$
$$q = 3$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 2$$
$$x_{1} x_{2} = 3$$
The graph
Sum and product of roots [src]
sum
        ___           ___
1 - I*\/ 2  + 1 + I*\/ 2 
$$\left(1 - \sqrt{2} i\right) + \left(1 + \sqrt{2} i\right)$$
=
2
$$2$$
product
/        ___\ /        ___\
\1 - I*\/ 2 /*\1 + I*\/ 2 /
$$\left(1 - \sqrt{2} i\right) \left(1 + \sqrt{2} i\right)$$
=
3
$$3$$
3
Rapid solution [src]
             ___
x1 = 1 - I*\/ 2 
$$x_{1} = 1 - \sqrt{2} i$$
             ___
x2 = 1 + I*\/ 2 
$$x_{2} = 1 + \sqrt{2} i$$
x2 = 1 + sqrt(2)*i
Numerical answer [src]
x1 = 1.0 + 1.4142135623731*i
x2 = 1.0 - 1.4142135623731*i
x2 = 1.0 - 1.4142135623731*i
The graph
-x^2+2*x-3=0 equation