判别式

判別式

pànbiéshì

noun

Meanings

1 discriminant (mathematics)
2 expression used to determine the nature of roots (e.g. b² − 4ac for a quadratic)

Characters

to distinguish, differentiate

formula, expression

Examples

二次方程的判别式大于零，说明有两个不同的实数根。

Èrcì fāngchéng de pànbiéshì dàyú líng, shuōmíng yǒu liǎng gè bùtóng de shíshù gēn.

When the quadratic equation's discriminant is greater than zero, it has two distinct real roots.

请先计算判别式，再决定用哪种方法。

Qǐng xiān jìsuàn pànbiéshì, zài juédìng yòng nǎ zhǒng fāngfǎ.

First calculate the discriminant, then decide which method to use.

Tips

memory

判 (judge) + 别 (distinguish) + 式 (formula) — literally 'judging-distinguishing formula.' For ax² + bx + c = 0, that's Δ = b² − 4ac, the value that judges whether the roots are real, repeated, or complex.

Stroke Order

判 pàn

别 bié

式 shì