hyperbolic functions

hyperbolic functions, the hyperbolic sine of z (written sinh z); the hyperbolic cosine of z (cosh z); the hyperbolic tangent of z (tanh z); and the hyperbolic cosecant, secant, and cotangent of z. These functions are most conveniently defined in terms of the exponential function, with sinh z = 1/2(e^z − e^−z) and cosh z = 1/2(e^z + e^−z) and with the other hyperbolic trigonometric functions defined in a manner analogous to ordinary trigonometry. Just as the ordinary sine and cosine functions trace (or parameterize)...