Trig identities part 2 (parr 4 if you watch the proofs)

Learn more: http://www.khanacademy.org/video?v=ZWSoyUxAQW0
More playing around with trig identities

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Length: 8 minutes

Trig identies part 3 (part 5 if you watch the proofs)

Length: 9 minutes

Trigonometry word problems (part 1)

Length: 2 minutes

Trigonometry word problems (part 2)