Find all real and imaginary solutions to the equation calculator

Summary :

The complex number equation calculator returns the complex values for which the quadratic equation is zero.

complexe_solve online

Description :

This calculator allows to find the complex roots of a quadratic equation like this: `x^2+1=0`. To solve this equation just enter the expression x^2+1=0 and press calculate button.

Syntax :

complexe_solve(equation;variable)

Examples :

Calculate online with complexe_solve (solving quadratic equation with complex number)

Calculator Use

This online calculator is a quadratic equation solver that will solve a second-order polynomial equation such as ax2 + bx + c = 0 for x, where a ≠ 0, using the quadratic formula.

The calculator solution will show work using the quadratic formula to solve the entered equation for real and complex roots. Calculator determines whether the discriminant \( (b^2 - 4ac) \) is less than, greater than or equal to 0.

 When \( b^2 - 4ac = 0 \) there is one real root.

 When \( b^2 - 4ac > 0 \) there are two real roots.

 When \( b^2 - 4ac < 0 \) there are two complex roots.

Quadratic Formula:

The quadratic formula

\( x = \dfrac{ -b \pm \sqrt{b^2 - 4ac}}{ 2a } \)

is used to solve quadratic equations where a ≠ 0 (polynomials with an order of 2)

\( ax^2 + bx + c = 0 \)

Examples using the quadratic formula

Example 1: Find the Solution for \( x^2 + -8x + 5 = 0 \), where a = 1, b = -8 and c = 5, using the Quadratic Formula.

\( x = \dfrac{ -b \pm \sqrt{b^2 - 4ac}}{ 2a } \)

\( x = \dfrac{ -(-8) \pm \sqrt{(-8)^2 - 4(1)(5)}}{ 2(1) } \)

\( x = \dfrac{ 8 \pm \sqrt{64 - 20}}{ 2 } \)

\( x = \dfrac{ 8 \pm \sqrt{44}}{ 2 } \)

The discriminant \( b^2 - 4ac > 0 \) so, there are two real roots.

Simplify the Radical:

\( x = \dfrac{ 8 \pm 2\sqrt{11}\, }{ 2 } \)

\( x = \dfrac{ 8 }{ 2 } \pm \dfrac{2\sqrt{11}\, }{ 2 } \)

Simplify fractions and/or signs:

\( x = 4 \pm \sqrt{11}\, \)

which becomes

\( x = 7.31662 \)

\( x = 0.683375 \)

Example 2: Find the Solution for \( 5x^2 + 20x + 32 = 0 \), where a = 5, b = 20 and c = 32, using the Quadratic Formula.

\( x = \dfrac{ -b \pm \sqrt{b^2 - 4ac}}{ 2a } \)

\( x = \dfrac{ -20 \pm \sqrt{20^2 - 4(5)(32)}}{ 2(5) } \)

\( x = \dfrac{ -20 \pm \sqrt{400 - 640}}{ 10 } \)

\( x = \dfrac{ -20 \pm \sqrt{-240}}{ 10 } \)

The discriminant \( b^2 - 4ac < 0 \) so, there are two complex roots.

Simplify the Radical:

\( x = \dfrac{ -20 \pm 4\sqrt{15}\, i}{ 10 } \)

\( x = \dfrac{ -20 }{ 10 } \pm \dfrac{4\sqrt{15}\, i}{ 10 } \)

Simplify fractions and/or signs:

\( x = -2 \pm \dfrac{ 2\sqrt{15}\, i}{ 5 } \)

which becomes

\( x = -2 + 1.54919 \, i \)

\( x = -2 - 1.54919 \, i \)

calculator updated to include full solution for real and complex roots

Calculator Use

This calculator is a quadratic equation solver that will solve a second-order polynomial equation in the form ax2 + bx + c = 0 for x, where a ≠ 0, using the completing the square method.

The calculator solution will show work to solve a quadratic equation by completing the square to solve the entered equation for real and complex roots.

Completing the square when a is not 1

To complete the square when a is greater than 1 or less than 1 but not equal to 0, factor out the value of a from all other terms.

For example, find the solution by completing the square for:

\( 2x^2 - 12x + 7 = 0 \)

\( a \ne 1, a = 2 \) so divide through by 2

\( \dfrac{2}{2}x^2 - \dfrac{12}{2}x + \dfrac{7}{2} = \dfrac{0}{2} \)

which gives us

\( x^2 - 6x + \dfrac{7}{2} = 0 \)

Now, continue to solve this quadratic equation by completing the square method.

Completing the square when b = 0

When you do not have an x term because b is 0, you will have a easier equation to solve and only need to solve for the squared term.

For example: Solution by completing the square for:

\( x^2 + 0x - 4 = 0 \)

Eliminate b term with 0 to get:

\( x^2 - 4 = 0 \)

Keep \( x \) terms on the left and move the constant to the right side by adding it on both sides

\( x^2 = 4\)

Take the square root of both sides

\( x = \pm \sqrt[]{4} \)

therefore

\( x = + 2 \)

\( x = - 2 \)

The calculator will try to find the zeros (exact and numerical, real and complex) of the linear, quadratic, cubic, quartic, polynomial, rational, irrational, exponential, logarithmic, trigonometric, hyperbolic, and absolute value function on the given interval.

Your input: solve the equation $$$x^{4} - 16 x^{3} + 90 x^{2} - 224 x + 245=0$$$ for $$$x$$$ on the interval $$$\left( -\infty,\infty \right )$$$

Answer

Real roots

$$$x=5$$$

$$$x=7$$$

Complex roots

$$$x=2 + \sqrt{3} i\approx 2.0 + 1.73205080756888 i$$$

$$$x=2 - \sqrt{3} i\approx 2.0 - 1.73205080756888 i$$$

Is there a calculator that solves algebra?