Sine and cosine of complementary angles

Learn about the relationship between the sine of an angle and the cosine of its complementary angle, which is the angle that completes to 90°.

Intro to the Pythagorean trig identity

Sine & cosine of complementary angles

Using complementary angles

Relate ratios in right triangles

Trig word problem: complementary angles

Trig challenge problem: trig values & side ratios