# Introducing Trig functions

Author:
Miss Evans, azb
Topic:
Functions
We have three trigonometric functions: sine, cosine and tangent. These are commonly abbreviated to 'sin' 'cos' and 'tan'. Trigonometric functions work with angles.
Move the right angle and change the value of . Look at what happens with the calculations

How do the trig functions relate to the ratio of sides?

## Cosine

Is cos () =

Tick all that apply

## Tangent

Is tan () =

Tick all that apply

## Sine

Is sin () =

Tick all that apply

## SOHCAHTOA

SOHCAHTOA is used in Trigonometry to help us remember the functions. What does it mean? Hint: how does it relate to the above ratios?

Make a note of SOHCAHTOA so you can remember how to use it on the next activity.