Let’s try using our trigonometric identities to solve word problems, including ones featuring bearings.

Examples

A man sets off from his house and walk 6km on a bearing of 090º before stopping at a cafe. He then walks 10km North to his friends house. What bearing should he follow to get home? And how long would it take him if he travels at a speed of 4km/h?

An isosceles triangle has a base length of 6cm and side lengths of 10cm. What are each of the angles in the triangle?

IF WE KNOW THE COSINE RULE ALREADY: A ship sails 22km from A on a bearing of 042º and a further 30km on a bearing of 090º to arrive at B. What is the distance and bearing of B from A?

Exercise

Let’s complete exercise 5 from pages 217 to 219 of the extended textbook:

The answers are below:

Further Mixed Questions

Answers