Syntax. COSH(number)
Definition. This function returns the hyperbolic cosine of a number.
Argument
number (required) Any real number.
Background. The hyperbolic cosine belongs to the hyperbolic functions, which are (like the circle functions) defined for all real and complex numbers. (However, Excel allows only real arguments, not complex arguments, for hyperbolic functions.) The hyperbolic cosine is defined as follows:
A hyperbolic cosine is shown in Figure 16-13.
Figure 16-13. The hyperbolic cosine is an even function symmetrical to the y-axis because it has two monotonic intervals.
The hyperbolic cosine is often used for research and development in engineering and natural sciences. The hyperbolic cosine is best known as catenary. The catenary describes the form of a freely suspended chain affixed at two points. The equation for the catenary is:
α is the distance between the apex and the zero line (lowest point).