PreCalculus - Trigonometry (15 of 54) Fundamental Trig Idenities

In this video I will derive the basic fundamental trig identities.

[blk-ozzy]

Incredibly incredibly helpful series, thank you so much! You have a way of explaining concepts that makes them "click" and make sense.

[becnal]

I love your videos. Could you do one on how irrational sine values are found, both by ancients such as Ptolemy and Ulugh Beg, as well as by modern calculators using power series?

[AbercrombieandBitch]

Hey Micheal, I love your videos. They've been immensely helpful in pre-calc. Out of curiosity, how many purple shirts do you own?