C/math.h/expm1

expm1: returns the natural logarithm e raised to the arg power, minus 1( e^arg-1)

<source lang="cpp">

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.*/

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