Algebraic expressions can be simplified by multiplying out the brackets and collecting like terms, or by factorising with a common factor. Straight line gradients can be calculated using a formula.

A sequence is a set of numbers that are connected in some way. In this section, we will learn how to recognise different types of sequences, extend a number or diagrammatic pattern and determine its formula.

A sequence is a list of numbers. The numbers are called the terms of the sequence.

There are many well-known sequences of numbers which you should be able to recognise.