The mathematical formula of δ is: δ = b? -4ac. Mathematical△ denotes the discriminant of roots. The discriminant of roots is a formula for judging the number of real roots of an equation, which is widely used in solving problems, involving the range of solution coefficients, judging the number and distribution of roots of an equation and so on. Univariate quadratic equation ax? The discriminant of the root of +bx+c=0(a≠0) is b? -4ac, represented by "△" (pronounced "delta").

The discriminant of roots is a formula to judge the number of real roots of an equation. Pronunciation of the fourth Greek letter of δ, uppercase δ, lowercase δ. In mathematics or physics, the capitalized δ is used to represent the incremental symbol. And lowercase δ is usually used to represent variables or symbols in higher mathematics.

In the unary quadratic equation ax? +bx+c=0(a≠0):

1, when △ > 0, the equation has two unequal real roots;

2. When △=0, the equation has two equal real roots;

3. When △

In the unary quadratic equation ax? +bx+c=0(a≠0, a, b and c are imaginary numbers):

1, when δ≥ 0, this equation has two equal complex roots;

2. When δ