Delta is the pronunciation of the fourth Greek letter, capitalized as δ and lowercase as 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 algebra, δ is used as a discriminant to represent the root of an equation. Discriminant of quadratic equation in one variable: δ = b? -4ac, when δ > 0, the equation has two unequal real roots; When δ = 0, the equation has two equal real roots; When δ

Operation symbol:

Such as plus sign (+), minus sign (-), multiplication sign (× or), division sign (÷ or/), union of two sets (∩), intersection (∩), root sign (∩ ~), logarithm (log, lg, ln,

Relational character

For example, "=" is an equal sign, "≈" is an approximate sign, "≦" is an unequal sign and ">" is a greater than sign. "