lispdoc  results for acosh 
(acosh number)  Function: Return the hyperbolic arc cosine of NUMBER.

Mentioned in: CLtL2  12.1. Precision, Contagion, and Coercion CLtL2  12.5.2. Trigonometric and Related Functions CLtL2  12.5.3. Branch Cuts, Principal Values, and Boundary Conditions in the Complex Plane HyperSpec  Function SINH, COSH, TANH, ASINH, ACOSH, ATANH PCL  higher math  
(cosh number)  Function: Return the hyperbolic cosine of NUMBER.

Mentioned in: CLtL2  12.5.2. Trigonometric and Related Functions CLtL2  12.5.3. Branch Cuts, Principal Values, and Boundary Conditions in the Complex Plane HyperSpec  Function SINH, COSH, TANH, ASINH, ACOSH, ATANH PCL  higher math  
By Bill Moorier 