Polar Coordinates 1
http://www.youtube.com/watch?v=jexMSlSDubMJane's Comment:
Dear Mr. Khan, the reason I stopped by is because someone asked me to make tutorials on Polar Coordinates. You must know that the polar point (5, 53.13°) is only close to the Cartesian point (3, 4). Those two points are NOT EQUAL. Rover would have never reached Mars. I have restrained from writing for a long time. Math cannot be sloppy. Do not mean to offend. But students must learn properly.
P.S. Your sine double angle proof would turn off anyone going into math.
