# \theta

The θ symbol (Greek small letter theta, U+03B8), written as \theta in LaTeX math mode.

https://texform.dev/latex/symbols/theta

## Metadata

| Field | Value |
| --- | --- |
| Topic | [Greek letters](https://texform.dev/latex/topics/greek) |
| Packages | base |
| Allowed mode | math |
| Glyph | θ |
| Unicode | U+03B8 GREEK SMALL LETTER THETA |
| Delimiter | No |

## Syntax

```latex
\theta
```

Takes no arguments.

## Common tasks

### How to write a Greek theta

```latex
\theta
```

[Open in Playground](https://play.texform.dev/?input=%5Ctheta)

### How to write a polar angle

```latex
x=r\cos\theta
```

[Open in Playground](https://play.texform.dev/?input=x%3Dr%5Ccos%5Ctheta)

### How to write a Heaviside step

The step function is often uppercase \Theta; the angle is \theta.

```latex
\Theta(x)
```

[Open in Playground](https://play.texform.dev/?input=%5CTheta%28x%29)

## Usage frequency

5.69% of formulas in the measured corpus contain this entry, rank 17 of 474 entries with frequency data.

## In TeXForm

TeXForm parses this entry as a character leaf mapped to U+03B8 (GREEK SMALL LETTER THETA).