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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
(x2−3x)+4=0\left(x^{2} - 3 x\right) + 4 = 0
Simplify
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:
x1=D−b2ax_{1} = \frac{\sqrt{D} - b}{2 a}
x2=−D−b2ax_{2} = \frac{- \sqrt{D} - b}{2 a}
where D = b^2 - 4*a*c - it is the discriminant.
Because
a=1a = 1
b=−3b = -3
c=4c = 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
x1=32+7i2x_{1} = \frac{3}{2} + \frac{\sqrt{7} i}{2}
x2=32−7i2x_{2} = \frac{3}{2} - \frac{\sqrt{7} i}{2}
Vieta's Theorem
it is reduced quadratic equation
px+q+x2=0p x + q + x^{2} = 0
where
p=bap = \frac{b}{a}
p=−3p = -3
q=caq = \frac{c}{a}
q=4q = 4
Vieta Formulas
x1+x2=−px_{1} + x_{2} = - p
x1x2=qx_{1} x_{2} = q
x1+x2=3x_{1} + x_{2} = 3
x1x2=4x_{1} x_{2} = 4
The graph
012345678-3-2-1020
Plot the graph f1(x)
Plot the graph f2(x)
Rapid solution [src] 
             ___
     3   I*\/ 7 
x1 = - - -------
     2      2
x1=32−7i2x_{1} = \frac{3}{2} - \frac{\sqrt{7} i}{2} 
             ___
     3   I*\/ 7 
x2 = - + -------
     2      2
x2=32+7i2x_{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
(32−7i2)+(32+7i2)\left(\frac{3}{2} - \frac{\sqrt{7} i}{2}\right) + \left(\frac{3}{2} + \frac{\sqrt{7} i}{2}\right) 
=
3
33 
product
/        ___\ /        ___\
|3   I*\/ 7 | |3   I*\/ 7 |
|- - -------|*|- + -------|
\2      2   / \2      2   /
(32−7i2)(32+7i2)\left(\frac{3}{2} - \frac{\sqrt{7} i}{2}\right) \left(\frac{3}{2} + \frac{\sqrt{7} i}{2}\right) 
=
4
44 
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
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