Trigonometry

There are two parts to the trigonometry course.

The first part relates to finding missing sides and angles or the area of a triangle:

• application of the trigonometric ratios for sin, cos and tan (sin=opp/hyp etc.) for right-angled triangles
• application of the sine rule for cases where you have one complete and one incomplete "angle and opposite side" pair
• application of cosine rule where you have 2 sides and the angle between them, or just 3 sides of a triangle
• application of area of triangle rule 1/2 ab SinC

This is relatively straightforward and covers about 90% of the questions that come up on the exam.

The second part relates to compound angles, angles > 90 degrees, compass directions, unit circle, handling special angles (30, 45 and 60 degrees) using surds. This is the second half of the chapter.

In today's class we went through the 2007 trigonometry question which involved material from the first list above. You have to go back quite a few years to find a question that involves compound angles, angles which are > 90 degrees etc.

Homework for tonight was the 2006 Trig question.

In tomorrow's class we will tackle the second part of the trigonometry course.
In the second period, we'll start revising Algebra.