C/math.h/expm1

    
Declaration: float expm1f(float arg); 
             double expm1(double arg); 
             long double expm1l(long double arg);  
 
  
  #include <math.h>
  #include <stdio.h>
  int main(void)
  {
     printf("Value of e to the first: %f.", expm1f(1.0));
  }
         
/*
Value of e to the first: 1.718282.*/