Khan/khan-exercises — pull request #38362 by ramyarangan (2013-01-19 05:25:01+00:00)
Title: Added new exercise graphs_of_tangent

This exercise, modeled after the exercise graphs_of_sine_and_cosine.html, allows students to learn about tangent graphs. Created in response to the Trello card: https://trello.com/c/Odl0jAdX.