Task 4 and 5 are done

2025.05.09/04Ex/solve.c

@@ -3,12 +3,24 @@
 #include <math.h>
 #include <float.h>
 
-int t3_solve (
+double t4_solve (
 		double (*f) (double), 
-		double x, double h 
+		double a, double b,
+		int n	
 ) {
-	if (h < DBL_EPSILON)
+	const double h = (b - a) / n;
+	double x = a;
+	double sum = (f(a) + f(b)) * 0.5;
+
+	if (h < NUM_FPE)
 		return DBL_MAX;
-	return (f(x + h) - 2 * f(x) + f(x - h)) / (h * h);
+	
+	for (int i = 1; i < (n - 1); ++i)
+	{
+		x += h;
+		sum += f(x);
+	}
+
+	return h * sum;
 }