1. CHAPTER 4 TRIGONOMETRIC FUNCTIONS
Jungeun Park
Reem Malak
MARY OGUNKORODE
CHAPTER 4 TRIGONOMETRIC FUNCTIONS
Section 3
Right Triangle Trigonometry

2. THE RIGHT TRIANGLE
Hypotenuse
Opposite to θ ( θ
Adjacent to θ

3. The Six Trigonometric Functions
1. Sine (sin)
2. Cosecant (csc)
3. Cosine (cos)
4. Secant (sec)
5. Tangent (tan)
6. Cotangent (cot)

4. Right Triangle Definitions of Trigonometric Functions
sin θ = opp/hyp
cos θ = adj/hyp
tan θ =opp/adj
csc θ = hyp/opp
sec θ = hyp/adj
cot θ =adj/opp

5. Example #1 (Booyakasha!)
SOLUTION
By the Pythagorean Theorem,
(hyp)^2 = (opp)^2 + (adj)^2
hyp =
sin θ = opp/hyp = 12/15 = 4/5
csc θ = hyp/opp = 5/4
cos θ = adj/hyp = 3/5
sec θ = hyp/adj = 5/3
tan θ = opp/adj = 4/3
cot θ = adj/opp = 3/4
Hypotenuse 12 θ 9

6. Do it yourself!
Solve for the missing side using the Pythagorean Theorem. Then find the six trigonometric functions. 25 20