ATANH INDEX

ATANH _ _ _ _ _ _ _ _ _ _ _ _ operator

The atanh operator returns the hyperbolic arctangent of its argument. The derivative of asinh and some simple transformations are known to the system.

syntax:

atanh(<expression>) or atanh <simple\_expression>

<expression> may be any scalar REDUCE expression, not an array, matrix or vector expression. <simple\_expression> must be a single identifier or begin with a prefix operator name.

examples:


atanh aa; 

  ATANH(AA) 


atanh(1); 

  ATANH(1) 


df(atanh(x*y),y); 

     - X
  ----------
   2  2
  X *Y  - 1

A numeric value is not returned by asinh unless the switc h rounded is on and its argument evaluates to a number. You may attach additional functionality by defining atanh to be the inverse of tanh. This is done by the commands


        put('tanh,'inverse,'atanh);
        put('atanh,'inverse,'tanh);