The function call pow(a, b) is used to evaluate ab, The pow function gives a domain error if the value of a is zero and b is less than or equal to zero or if a is negative and b is not an integer.
#include <stdio.h>
#include <math.h>
main()
{
double a= 2.0;
double b= 3.0;
printf("%f^%f=%f",a,b,pow(a,b));
}