Expert: Richard J. Raridon - 1/3/2005

Question
Can hyperbolic functions be defined on the basis of geometry, like trigonometric functions are defined as the ratios between sides of a right angled triangle? I only know the definition based on the exponential function.Why are they called HYPERBOLIC functions?

Answer
If you go to a dictionary, you can find the following:
hyperbolic function - any of a set of six functions analogous to the trigonometric functions but related to the hyperbola in a way similar to that in which the trigonometric functions are related to a circle