Hyperbolic functions post 35

[EdS2]

The only thought I have about the usefulness of hyperbolic functions is something vague about the catenary function - but hanging cables or chains across gaps is a very real-world thing to do.

A bit of web-searching turns up this

Quote:They are very useful in relativistic physics. Cosh and Sinh are the Lorentzian geometry analogs of Cos and Sin. Just like rotations preserve distances in the plane and can be written in terms of "cos" and "sin", there are transformations in Lorentzian geometry which preserve "proper time", the analog of distance, and are written in terms of "cosh" and "sinh".

and

Quote:I'd say they are most important in differential equations. The very simple equation y'' = ky shows up in many many places, and the solutions are sinh and cosh when k is positive.

But as a kid with an interest in calculators, I remember noticing the Casio machines had these extra functions, compared to mine.