It’s easy to work out the area of a simple right angled triangle. But what do you do when you’re faced with an irregular shaped triangle. Read on to find out.

## Trigonometry

## Cosine Rule

In addition to the Sine Rule, we also have another Trigonometrical Formula we can use to help find the lengths of sides and size of angles, This is called the Cosine Rule.

## Inverse Trigonometric Functions

Inverse Trigonometric Functions are essential to solving trigonometrical questions involving finding angles. Read on to find out how to use them correctly.

## Pythagoras’ Theorem

Pythagoras’ Theorem is one of the oldest and well known theorems known today. The reason for this is probably how simple, yet extremely useful it is in so many branches of Mathematics.

## Sine Rule

As well as the usual Sine, Cosine and Tangent Formulas for right angled triangles, there’s also a handy little formula that you can use for any triangle. This is known as the Sine Rule and can be used to find the size of the angles or the lengths of a side.

## Sine, Cosine & Tangent

Trigonometry is one of the oldest and yet most useful branches of mathematical study. Read on to see why.