public class Eqn1 implements NewtonRaphson {

  public double f(double x) {
    return x*x*x + x*x - 17*x + 15;
  }

  public double fdash(double x) {
    return 3*x*x + 2*x - 17;
  }

  public static void usage() {
    System.err.println("Usage: java Eqn1 <start-x>");
  }

  public static void main(String[] args) {

    // Check if start-x argument is given
    if(args.length != 1) {
      usage();
      System.exit(1);
    }

    double start = 0;
    try {
      start = Double.parseDouble(args[0]);
    } catch(NumberFormatException nfe) {
      System.err.println(nfe.getMessage());
      usage();
      System.exit(2);
    }

    Eqn1 eqnInst = new Eqn1();
    NR nrInst = new NR(eqnInst);
    System.out.println("Solution is x="+nrInst.solve(start));

  } // End main()

} // End class Eqn1