dora_pr5_3

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define N 30

double integral(double a, double b, int n, double (*f)(double)){
    double s=(f(a)+f(b))/2;
    double h=(b-a)/n;
    for (int i=1; i<=n-1; i++)
    {
        s+=f(a+i*h);
    }
    return h*s;
}

double f1(double x)
{
    return 2*x *(x*x + 1);
}

double f2(double x)
{
    return log(x*x + 1);
}

int main()
{

printf("First integral = %.2lf\n", integral(-1, 4, N, f1));
printf("Second integral = %.2lf\n", integral(1, 4, N, f2));
return 0;
}