mirror of https://github.com/TheAlgorithms/C
42 lines
836 B
C
42 lines
836 B
C
#include <math.h>
|
|
#include <stdio.h>
|
|
|
|
float f(float x)
|
|
{
|
|
return 1.0 +
|
|
x * x * x; // This is the expresion of the function to integrate?
|
|
}
|
|
|
|
int main()
|
|
{
|
|
int i, n;
|
|
float a, b, h, x, s2, s3, sum, integral;
|
|
|
|
printf("enter the lower limit of the integration:");
|
|
scanf("%f", &a);
|
|
printf("enter the upper limit of the integration:");
|
|
scanf("%f", &b);
|
|
printf("enter the number of intervals:");
|
|
scanf("%d", &n);
|
|
|
|
h = (b - a) / n;
|
|
sum = f(a) + f(b);
|
|
s2 = s3 = 0.0;
|
|
|
|
for (i = 1; i < n; i += 3)
|
|
{
|
|
x = a + i * h;
|
|
s3 = s3 + f(x) + f(x + h);
|
|
}
|
|
|
|
for (i = 3; i < n; i += 3)
|
|
{
|
|
x = a + i * h;
|
|
s2 = s2 + f(x);
|
|
}
|
|
|
|
integral = (h / 3.0) * (sum + 2 * s2 + 4 * s3);
|
|
printf("\nValue of the integral = %9.4f\n", integral);
|
|
|
|
return 0;
|
|
} |