static double Rectangle(Integrand f, int steps)
{
double step = (f.RightBound - f.LeftBound) / steps;
double sum = 0;
for (int i = 0; i < steps; ++i)
{
sum += f.Function(f.LeftBound + step / 2 + i * step);
}
return(sum * step);
}
static double Trapeze(Integrand f, int steps)
{
double step = (f.RightBound - f.LeftBound) / steps;
double sum = 0;
double i;
for (i = f.LeftBound; i + step <= f.RightBound; i += step)
{
sum += step * (f.Function(i) + f.Function(i + step)) / 2;
}
if (i != f.RightBound)
{
sum += (f.RightBound - i) * (f.Function(i) + f.Function(f.RightBound)) / 2;
}
return(sum);
}