//实现Simpson 3/8法则 #include #include

using namespace std;

class simpson2 { private:  int n, k;  double a, b, f, integral, interval, one_third_interval;  double sum_term1, sum_term2, sum_term3, x;

public:  double func(double x)  {   f = (5.093e-5 * exp(2 * x)) / pow((1 + x * x), 2);   return f;  }  void integration(); };

void main() {  simpson2 simp2;  simp2.integration(); }

void simpson2::integration() {  cout > b >> a;  cout n;  interval = (b - a) / n;  one_third_interval = interval / 3.0;  sum_term1 = 0.0;  sum_term2 = 0.0;  sum_term3 = 0.0;  for (k = 1; k < n; k++)  {   x = a + k * interval;   sum_term1 += func(x);   sum_term2 += func(x + one_third_interval);   sum_term3 += func(x + 2 * one_third_interval);  }  integral = (2 * sum_term1 + 3 * sum_term2 + 3 * sum_term3 - func(a) + func(b)) * (3 * one_third_interval / 8);  cout