C/math.h/atanh

    
//Declaration: float atanhf(float arg); 
               double atanh(double arg); 
               long double atanhl(long double arg);  
//Parameter:   This argument must be in the range -1 to 1. 
  

  #include <math.h>
  #include <stdio.h>
  int main(void)
  {
    printf("%f.\n",  atanh(12));
    return 0;
  }
         
/*
-1.#IND00.
*/