6.2: Right angle trigonometryJanuary 6, 2009

ObjectivesLearn basic concepts about

trigonometric functionsApply right triangle trigonometryUnderstand complementary

angles and cofunctions.

Basics of Trigonometry Functionssin θ = O/Hcos θ = A/Htan θ = O/Acsc θ = H/Osec θ = H/Acot θ = A/O

Solving a triangleRemember the

Pythagorean theorem?

If a= 5 and c= 10, what is b?

Finding missing angles

c=17, a=8

What is sin θ?..cos θ?…tan θ?

Finding missing sidesc=10, β=60°

How long is b?

Complementary angles and cofunctionsA and B are

complementary.sin A=cos A=tan A=cot A=sec A=csc A=

Trig functions of a 45-45-90 triangle

Sin 45

Csc 45

Cos 45

Sec 45

Tan 45

Cot 45

Trig functions of a 30-60-90 triangle

θ Sin θ

Cos θ Tan θ Csc θ Sec θ Cot θ

30°

60°

Assignment

17-2833-3849-52