We will see radians, θ’s and π’s from time to time in calculus. Remember the unit circle, special right triangles, and all that jazz? Believe us—these will come in handy. Sines (sin), cosines (cos), and tangents (tan) will be regulars, as will be their inverses. Feel free to review them if you need a refresher.
We will also learn how to switch from polar to Cartesian coordinates. Pythagoras will suddenly become a very useful guy to know.