### Introduction

Indices, or powers, provide a convenient notation when we need to multiply a number by itself several times. In this Section we explain how indices are written, and state the rules which are used for manipulating them.

Expressions built up using non-negative whole number powers of a variable $-$ known as polynomials $-$ occur frequently in engineering mathematics. We introduce some common polynomials in this Section.

Finally, scientific notation is used to express very large or very small numbers concisely. This requires use of indices. We explain how to use scientific notation towards the end of the Section.

#### Prerequisites

• be familiar with algebraic notation and symbols

#### Learning Outcomes

• perform calculations using indices
• state and use the laws of indices
• use scientific notation