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x^2-3x+4=0

x^2-3x+4=0 equation

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Numerical solution:

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The solution

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

(-3)^2 - 4 * (1) * (4) = -7

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
$$x_{1} = \frac{3}{2} + \frac{\sqrt{7} i}{2}$$
$$x_{2} = \frac{3}{2} - \frac{\sqrt{7} i}{2}$$
Vieta's Theorem
it is reduced quadratic equation
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = -3$$
$$q = \frac{c}{a}$$
$$q = 4$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 3$$
$$x_{1} x_{2} = 4$$
The graph
Rapid solution [src]
             ___
     3   I*\/ 7 
x1 = - - -------
     2      2   
$$x_{1} = \frac{3}{2} - \frac{\sqrt{7} i}{2}$$
             ___
     3   I*\/ 7 
x2 = - + -------
     2      2   
$$x_{2} = \frac{3}{2} + \frac{\sqrt{7} i}{2}$$
x2 = 3/2 + sqrt(7)*i/2
Sum and product of roots [src]
sum
        ___           ___
3   I*\/ 7    3   I*\/ 7 
- - ------- + - + -------
2      2      2      2   
$$\left(\frac{3}{2} - \frac{\sqrt{7} i}{2}\right) + \left(\frac{3}{2} + \frac{\sqrt{7} i}{2}\right)$$
=
3
$$3$$
product
/        ___\ /        ___\
|3   I*\/ 7 | |3   I*\/ 7 |
|- - -------|*|- + -------|
\2      2   / \2      2   /
$$\left(\frac{3}{2} - \frac{\sqrt{7} i}{2}\right) \left(\frac{3}{2} + \frac{\sqrt{7} i}{2}\right)$$
=
4
$$4$$
4
Numerical answer [src]
x1 = 1.5 + 1.3228756555323*i
x2 = 1.5 - 1.3228756555323*i
x2 = 1.5 - 1.3228756555323*i
The graph
x^2-3x+4=0 equation