root in c

1#include <stdio.h>
2#include <math.h>
3
4int main()
5{
6    double num = 6, squareRoot;
7
8    squareRoot =  sqrt(num);
9    printf("Square root of %lf =  %lf", num, squareRoot);
10
11    return 0;
12}

1double sqrt(double arg);