1. Introduction to Trigonometric Functions
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2. Trig functions are the relationships amongst various sides in right triangles.
You know by the Pythagorean theorem that the sum of the squares of each of the smaller sides equals the square of the hypotenuse,

3. You know in the above triangle thatc b C B a
You know in the above triangle that
Trig functions are how the relationships amongst the lengths of the sides of a right triangle vary as the other angles are changed.

4. How does this relate to trig?
sin(θ) = b/c
cos(θ) = a/c
tan(θ)= b/a c b θ C B a

5. Remember SOHCAHTOA Sine: Opposite/ Hypotenuse
Cosine: Adjacent/ Hypotenuse
Tangent: Opposite/ Adjacent

6. Practice!?
c=?
sin(θ)=
cos(θ)=
tan(θ)= A c 3 θ C B 4

7. Practice!?
b=?
sin(θ)=
cos(θ)=
tan(θ)= θ 15 9 b

8. New Trig!
sin(θ)=
cos(θ)=
tan(θ)=
csc(θ)=
sec(θ)=
cot(θ)=

9. More Practice! sin(θ)= cos(θ)= tan(θ)= csc(θ)= sec(θ)= cot(θ)= θ 15 912
csc(θ)=
sec(θ)=
cot(θ)=

10. More Practice! sin(θ)= cos(θ)= tan(θ)= csc(θ)= sec(θ)= cot(θ)= 15 9 θ12
csc(θ)=
sec(θ)=
cot(θ)=

11. Time for a worksheet!