# Trigonometry

#### Trigonometry covers the relationships between lengths and angles of triangles. Created by Khan Academy.Recommended that you have a good foundation in Geometry before taking this course.

8 hours

Intermediate

##### Pick a lesson

1: Basic Trigonometry
2: Basic Trigonometry II
3: Radians and degrees
4: Using Trig Functions
5: Using Trig Functions Part II
6: The unit circle definition of trigonometric function
7: Unit Circle Definition of Trig Functions
8: Graph of the sine function
9: Graphs of trig functions
10: Graphing trig functions
11: More trig graphs
12: Determining the equation of a trigonometric function
13: Trigonometric Identities
14: Proof: sin(a+b) = (cos a)(sin b) + (sin a)(cos b)
15: Proof: cos(a+b) = (cos a)(cos b)-(sin a)(sin b)
16: Trig identities part 2 (parr 4 if you watch the proofs)
17: Trig identies part 3 (part 5 if you watch the proofs)
18: Trigonometry word problems (part 1)
19: Trigonometry word problems (part 2)
20: Law of cosines
21: Navigation Word Problem
22: Proof: Law of Sines
23: Ferris Wheel Trig Problem
24: Ferris Wheel Trig Problem (part 2)
25: Fun Trig Problem
26: Polar Coordinates 1
27: Polar Coordinates 2
28: Polar Coordinates 3
29: Inverse Trig Functions: Arcsin
30: Inverse Trig Functions: Arctan
31: Inverse Trig Functions: Arccos
32: Trigonometry Identity Review/Fun
33: Tau versus Pi
34: IIT JEE Trigonometry Problem 1
35: IIT JEE Trigonometric Maximum
36: IIT JEE Trigonometric Constraints
37: Trigonometric System Example
38: 2003 AIME II Problem 11
39: 2003 AIME II Problem 14