# Capital C Symbol

The capital Latin letter C is used in mathematics as a variable. For example, it appears in geometric formulas as a variable representing the circumference of a circle. It also is used to represent the set of complex numbers displayed using a “double-struck” typeface.

Symbol Format Data
C Unicode
67

TeX
C
SVG

### Usage

Circumference of Circle | Formula

The circumference of a circle is given the constant τ (tau) multpilied by the radius of the circle, where τ = 2π.

Set of Complex Numbers | Concept

The set of complex numbers contains all possible complex numbers. Each complex number has a real part and an complex part.

### Related Symbols

C | Symbol

The latin letter c is used to represent a variable or coefficient.