Mister Exam
Other calculators
-
How to use it?
- Equation:
-
Equation x/12+x/8+x=-29/6
-
Equation x^2+7x-18=0
- Equation x-y+2=0
-
Equation (x-11)*(-x+9)=0
- Express {x} in terms of y where:
- 13*x-18*y=-17
- 7*x+6*y=20
- -7*x-19*y=-18
- 5*x+12*y=18
- Factor squared:
- x^2+x+3
- Graphing y =:
- x^2+x+3
- Integral of d{x}:
-
x^2+x+3
-
Identical expressions
- x^ two +x+ three = zero
- x squared plus x plus 3 equally 0
- x to the power of two plus x plus three equally zero
- x2+x+3=0
- x²+x+3=0
- x to the power of 2+x+3=0
- x^2+x+3=O
-
Similar expressions
- x^2+x-3=0
- x^2-x+3=0
x^2+x+3=0 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
This equation is of the form
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
$$a = 1$$
$$b = 1$$
$$c = 3$$
, then
Because D<0, then the equation
has no real roots,
but complex roots is exists.
or
$$x_{1} = - \frac{1}{2} + \frac{\sqrt{11} i}{2}$$
$$x_{2} = - \frac{1}{2} - \frac{\sqrt{11} i}{2}$$
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
$$a = 1$$
$$b = 1$$
$$c = 3$$
, then
D = b^2 - 4 * a * c =
(1)^2 - 4 * (1) * (3) = -11
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
$$x_{1} = - \frac{1}{2} + \frac{\sqrt{11} i}{2}$$
$$x_{2} = - \frac{1}{2} - \frac{\sqrt{11} i}{2}$$
Vieta's Theorem
it is reduced quadratic equation
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = 1$$
$$q = \frac{c}{a}$$
$$q = 3$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = -1$$
$$x_{1} x_{2} = 3$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = 1$$
$$q = \frac{c}{a}$$
$$q = 3$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = -1$$
$$x_{1} x_{2} = 3$$
Rapid solution
[src]
____
1 I*\/ 11
x1 = - - - --------
2 2
$$x_{1} = - \frac{1}{2} - \frac{\sqrt{11} i}{2}$$
____
1 I*\/ 11
x2 = - - + --------
2 2
$$x_{2} = - \frac{1}{2} + \frac{\sqrt{11} i}{2}$$
x2 = -1/2 + sqrt(11)*i/2
Sum and product of roots
[src]
sum
____ ____ 1 I*\/ 11 1 I*\/ 11 - - - -------- + - - + -------- 2 2 2 2
$$\left(- \frac{1}{2} - \frac{\sqrt{11} i}{2}\right) + \left(- \frac{1}{2} + \frac{\sqrt{11} i}{2}\right)$$
=
-1
$$-1$$
product
/ ____\ / ____\ | 1 I*\/ 11 | | 1 I*\/ 11 | |- - - --------|*|- - + --------| \ 2 2 / \ 2 2 /
$$\left(- \frac{1}{2} - \frac{\sqrt{11} i}{2}\right) \left(- \frac{1}{2} + \frac{\sqrt{11} i}{2}\right)$$
=
3
$$3$$
3
Numerical answer
[src]
x1 = -0.5 + 1.6583123951777*i
x2 = -0.5 - 1.6583123951777*i
x2 = -0.5 - 1.6583123951777*i
The graph