•The equation ax2 + bx + c = 0 with a, b, c ∈ R and a ≠ 0 is called a quadratic unknown equation, and the numbers a, b, c are the coefficients of the equation. In the equation ax2 + bx + c = 0, the numbers that provide equality when written in place of the unknown x are called the roots of the equation, and the set formed by these roots is also called the solution set of the equation.
