### Why is tangent called "tangent" in trigonometry? (TANTON Mathematics)

And why is secant called "secant" and cosine called co - sine? Why these names? In this video I explain the connection between the tangent of an angle and a tangent line. Ditto for the secant of an angle and a secant line. BTW: Did you know that "sine" means "harbour" or "cove"?

Length:
06:42