Complementary angles add up to 90º. In the following window you can see angle B (in red) and its complementary angle, angle A (in green)

2.- What does the sine of angle A always coincide with? What about its cosine?

3.- Find a connection between the tangents of angle A and angle B.

Supplementary angles add up to 180º. In the following window you can see angle B (in red) and its supplementary angle, angle A (in green).

2.- What do the sine values of supplementary angles have in common? What about their cosine values?

3.- What's the relation between the tangents of supplementary angles?

4.- If an angle is found in the fourth quadrant which quadrant does its supplementary angle belong to? What about its complementary angle?

In the following window you can see that there is a difference of p radians between angles A and B.

1.- Change the size of angle A and watch how angle B also changes size.

2.- What do the sine values of angles A and B have in common? What about their cosine values?

3.- What's the relation between the tangents of angles A and B?

In the following window you can see angle B (in red) and its opposite angle, angle A (in green).

1.- Change the size of angle A and watch how its opposite angle also changes size.
Prove that B = 2p - A.

2.- What do the sine values of the opposite angles have in common? What about their cosine values?

3.- What's the relation between the tangents of two opposite angles?