Quadratic Equation with Complex Roots
Solve ax² + bx + c = 0 with the full quadratic formula worked out step by step: exact roots like (3 ± √5)/2 or −1 ± 2i, the discriminant, the vertex and the factored form.
Result
This page opens the quadratic equation solver preloaded with a = 1, b = 2, c = 5 — an equation whose discriminant is negative: D = 2² − 4·1·5 = −16. No real number squares to −16, so the parabola never crosses the x-axis and the two roots are complex conjugates.
The solver continues the quadratic formula into the complex numbers: √(−16) = 4i, so x = (−2 ± 4i)/2 = −1 ± 2i. The radical under the negative sign is simplified exactly like a real one (√(−12) becomes 2i√3), common factors are cancelled with 2a, and the result is stated in the standard a ± bi form with decimal approximations alongside.
Replace the prefilled example with any coefficients of your own: whenever D < 0 you will get the exact conjugate pair, and whenever D ≥ 0 the same steps produce the real roots instead — so the page doubles as a general check for 'solve over the complex numbers' homework.