The hyperbolic cosine of *z* in Math. Defined by

Real part on the real axis:

Imaginary part on the real axis is zero.

Real part on the imaginary axis:

Imaginary part on the imaginary axis is zero.

Real part on the complex plane:

Imaginary part on the complex plane:

Absolute value on the complex plane:

Related functions: sinh sech arccosh

Function category: hyperbolic functions