# Symbols:K

## Contents

## kilo-

- $\mathrm k$

The Système Internationale d'Unités symbol for the metric scaling prefix **kilo**, denoting $10^{\, 3 }$, is $\mathrm { k }$.

Its $\LaTeX$ code is `\mathrm {k}`

.

## Subgroup

- $K$

Frequently used, in conjunction with $H$, to represent a general subgroup of a given group $G$ when two such subgroups need to be discussed.

## Field

- $K$

One of the letters used as a variable denoting a general field.

## Field as Algebraic Structure

- $\struct {K, +, \circ}$

The full specification for a field, where $+$ and $\circ$ are respectively the addition and product operations.

The $\LaTeX$ code for \(\struct {K, +, \circ}\) is `\struct {K, +, \circ}`

.

## Kernel

- $K$

Often used to denote the kernel of a general homomorphism.

## Unit Vector

- $\mathbf k$

A unit vector, usually in the direction of the $z$-axis.

Hence it is usually aligned so as to be parallel to the vertical direction in a given frame of reference.

## Kilometre

- $\mathrm {km}$

The symbol for the **kilometre** is $\mathrm {km}$:

Its $\LaTeX$ code is `\mathrm {km}`

.