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  1. #include <iostream>
  2. #include <cmath>
  3. #include <iomanip>
  4.  
  5. using namespace std;
  6.  
  7. // Define the function f(x) = x^3 - x - 3
  8. double f(double x) {
  9.     return pow(x, 3) - x - 3;
  10. }
  11.  
  12. // Define the derivative f'(x) = 3x^2 - 1
  13. double f_prime(double x) {
  14.     return 3 * pow(x, 2) - 1;
  15. }
  16.  
  17. int main() {
  18.     double x0 = 3.0; // Initial guess
  19.     double x1;
  20.     double tolerance = 1e-6;
  21.     int max_iterations = 100;
  22.     int iteration = 1;
  23.  
  24.     cout << fixed << setprecision(6);
  25.     cout << "**************************************" << endl;
  26.     cout << "ITERATION\tX\t\tf(X)\t\tf'(X)" << endl;
  27.     cout << "**************************************" << endl;
  28.  
  29.     while (iteration <= max_iterations) {
  30.         double fx = f(x0);
  31.         double fpx = f_prime(x0);
  32.  
  33.         if (fpx == 0.0) {
  34.             cout << "Derivative is zero. No solution found." << endl;
  35.             return -1;
  36.         }
  37.  
  38.         x1 = x0 - fx / fpx;
  39.  
  40.         cout << iteration << "\t\t" << x0 << "\t" << fx << "\t" << fpx << endl;
  41.  
  42.         if (fabs((x1 - x0) / x1) < tolerance) {
  43.             cout << "**************************************" << endl;
  44.             cout << "THE ROOT OF EQUATION IS " << x1 << endl;
  45.             break;
  46.         }
  47.  
  48.         x0 = x1;
  49.         iteration++;
  50.     }
  51.  
  52.     if (iteration > max_iterations) {
  53.         cout << "Did not converge to a solution within the maximum number of iterations." << endl;
  54.     }
  55.  
  56.     return 0;
  57. }
Success #stdin #stdout 0.01s 5288KB
comments (?)
stdin
copy 
x^0::-3
x^1::-1
x^2::0
x^3::1
stdout
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**************************************
ITERATION	X		f(X)		f'(X)
**************************************
1		3.000000	21.000000	26.000000
2		2.192308	5.344390	13.418639
3		1.794027	0.980105	8.655594
4		1.680793	0.067556	7.475195
5		1.671756	0.000411	7.384300
6		1.671700	0.000000	7.383742
**************************************
THE ROOT OF EQUATION IS 1.671700
https://ideone.com/8h5CqP
language:
C++14 (gcc 8.3)
created:
12 days ago
visibility:
public

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