HOW TO USE CALCULATOR
3.6. Quadratic equations
A polynomial in which the highest exponent is 2 is called a quadratic equation. Equate the quadratic expression to 0 and you get the standard form of the quadratic equation:
ax2 + bx + c = 0
In this equation, x represents a variable whereas a, b, and c are constants with a not equal to 0.
When you want to solve the quadratic equation you can select the [x^2+x] function from the Insert Function menu or simply write your equation in the form of ax^2 + bx + c = 0. Quadratic equations must have a x^2 member, while all other members of the equation are optional.
Because it is a second-order polynomial equation, the fundamental theorem of algebra guarantees that it has two solutions. These solutions may be both real, or both complex.
| Example | Result | Description |
|---|---|---|
| x^2+x-2=0 | x1 = 1; x2 = -2 | Two different real results |
| x^2+2x+1=0 | x1 = x2 = -1 | Only one result (double) |
| x^2 + 4x + 8 = 0 | x1 = x2 = Complex number | Non-real results |
Examples
4E-3x^2+3E-2x-2E-2=0 4x^2-3x-2 x^2+x-2=0 x^2-4
Citing this page:
Generalic, Eni. "C4C Help: Quadratic equations." EniG. Periodic Table of the Elements. KTF-Split, 27 Oct. 2022. Web. 2 Apr. 2025. <https://www.periodni.com/enig/c4c_help/quadratic_equations.html>.
