δ is the discriminant of quadratic equation in one variable. After transforming the unary quadratic equation into the general form of ax 2+bx+c = 0, δ = b 2-4ac.
Deduction process: The formula for finding the root of a quadratic equation with one variable is (b 2-4ac under the root sign of -b) divided by 2a.
If an unary quadratic equation has a real number root, then the internal formula under the root sign is greater than zero. So b 2-4ac is called discriminant, and the relationship with 0 determines whether the square capacity has real roots.
Extended data:
In algebra, δ is used as a discriminant to represent the root of an equation.
Discriminant of quadratic equation in one variable: δ = b? -4ac
① When δ > 0, the equation has two unequal real roots;
② When δ = 0, the equation has two equal real roots;
③ When δ
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