## Factorising

In this short video I show you what we mean by factorising.

The first step in factorising is:

ALWAYS check to see if the expression contains any common factors.

In this video, I demonstrate examples on factorising where there is a highest common factor (HCF).

Sometimes when there is no common factor, by grouping several of the terms together it is possible to factorise an expression.

Quadratic expressions have a distinct look about them. They have the form: ax^{2} + bx + c where a ≠ 0

When it comes to factorising a quadratic expression, there are particular methods depending on the form of the expression

In the tutorials which follow, I will show you how to factorise the above expressions.

## HCF types

Your first priority in factorising is to check to see if the quadratic expression has a common factor. In this tutorial I introduce you to what a quadratic expression is and then look at factorising quadratic expressions where there is a highest common factor (HCF).

## Difference of two squares type

Some quadratic expressions do not have a common factor but consist of two terms separated by a minus sign and each term is the square of something. This is known as the difference of 2 squares type. It has the form a^{2} – b^{2}

## Trinomials

Some quadratic expressions have 3 terms (trinomials) and no common factor yet can still be factorised.

There are two methods of factorising such expressions. 1) by grouping 2) by inspection. Which method you choose is up to you but I generally prefer method 2 as it can be quicker but requires a bit more practice.

### Method 1) – Trinomials Grouping Method

### (Method 2) – Trinomials Inspection Method

I now extend the work on factorising quadratic trinomials (3 terms) t