Materials regarding quadratic trig equations and tangent

How can I learn more about trigonometry? Does Khan Academy have more material in trigonometry about quadratic trigonometric equations, as well as practice problems on tangent identities, that I have not seen?

If not, how can I make the most of what they have while they continue making videos on those subjects (as I hope they will eventually do)?Will memorizing the trigonometric identities be enough for me to know how to solve trig equations?