math_1.cpp

math_1.cpp

#include <iostream>
#include <math.h>
#include <conio.h>
#define E 0.0001


using namespace std;

int main ()
{
  double step,x,y,sn,se,a;
  double n=0;
  y = 1;
  a = 0;
  se = 0;
  sn = 0;
  step = (1 - 0.1) /10;
  
  for (x=0.1;x<1;x+=step)
  { //precision
    while (abs(a)>E)
    {
      n++;
      a = (pow(-1,n+1)*pow(x,(2*n)+1))/((4*n*n)-1);
      se = se+a;
    };
    //n
    a = 0;
    for (int i = 0; i < 30; i++)
    {
      a = (pow(-1,n+1)*pow(x,(2*n)+1))/((4*n*n)-1);
      sn = sn+a;
    };
    y = ((1+x*x)/2* atan(x)) - x/2;
    cout << x << "\t" << se << "\t" <<sn << "\t" << y << "\n";
  }
  getch ();
}