Hey I'm a total beginner to Java and I could really use some help with this program please! This is part of the code I wrote. I put a do-while loop but this only takes care of the rootEstimate value, the powerRider value is also changing. Basically I need to end up with my answer for the root Estimate then after I got the answer with the first power, switch to the second power. The powerRider variable is declared as an array. I was thinking of possibly having a loop with an increment encasing the do-while loop which would increase whenever the while part is not met, but I'm not 100% sure how to approach this and some help would be appreciated! Code: function = -n*powerRider + 0.5*(rho*cD*area*(Math.pow(initialRootEstimate,3))) + (cR*m*g*initialRootEstimate); derivedFunction = (3/2)*(rho*cD*area*(Math.pow(initialRootEstimate,2))) + (cR*m*g); do { rootEstimate = initialRootEstimate - (function/derivedFunction); absDifference = Math.abs(rootEstimate-initalRootEstimate); numLoops++; initialRootEstimate=rootEstimate; } Thank you!

i m sending u a newton class..post ur sum...will let u know d solution... Code: class Newton { static double f(double x) { return Math.sin(x); } static double fprime(double x) { return Math.cos(x); } public static void main(String argv[]) { double tolerance = .000000001; // Our approximation of zero int max_count = 200; // Maximum number of Newton's method iterations /* x is our current guess. If no command line guess is given, we take 0 as our starting point. */ double x = 0; if(argv.length==1) { x= Double.valueOf(argv[0]).doubleValue(); } for( int count=1; (Math.abs(f(x)) > tolerance) && ( count < max_count); count ++) { x= x - f(x)/fprime(x); System.out.println("Step: "+count+" x:"+x+" Value:"+f(x)); } if( Math.abs(f(x)) <= tolerance) { System.out.println("Zero found at x="+x); } else { System.out.println("Failed to find a zero"); } } }

Hey sorry I've been working on it so haven't had a chance to check back. Thanks for the help! So far I've written this: Code: import java.io.*; public class Assignment1try2 { public static void main(String[] args) { //Exports the data to an excel file PrintWriter outputFile = null; try { outputFile = new PrintWriter(new FileOutputStream("outputVelomobile.xls",false)); } catch(FileNotFoundException e) { System.out.println("File error. Program aborted."); System.exit(0); } //Variable declarations for the Quest Velomobile double n = 0.92; double rho = 1.20; double cR = 0.004; double m = 32+80; double g = 9.81; double cD = 0.24; double area = 0.46; double valueOne = rho*cD*area; double valueTwo = cR*m*g; double initialRootEstimate = 1; double function, absDifference; double[] rootEstimate = new double[8]; int numLoops = 0; int[] powerRider = {25,50,75,100,150,200,300,400}; //Start loop for (int index=0;index<powerRider.length;index++) { numLoops = 0; do { function = -n*powerRider[index] + 0.5*(valueOne*(Math.pow(initialRootEstimate,3))) + (valueTwo*initialRootEstimate); rootEstimate[index] = initialRootEstimate - (function/((3/2)*(valueOne*(Math.pow(initialRootEstimate,2))) + (valueTwo))); absDifference = Math.abs(rootEstimate[index] - initialRootEstimate); initialRootEstimate = rootEstimate[index]; numLoops++; } while (absDifference >=1.0E-12); //Displays data on screen System.out.println(); System.out.println("The Power is:" + powerRider[index]); System.out.println("The Root Estimate is:" + initialRootEstimate); System.out.println("The number of cycles is:" + numLoops); System.out.println(); //Outputs results on screen outputFile.println(); outputFile.println("The Power is:" + powerRider[index]); outputFile.println("The Root Estimate is:" + initialRootEstimate); outputFile.println("The number of cycles is:" + numLoops); outputFile.println(); } outputFile.close(); } } It works but the only problem is that we end up with a lot of iterations. Is there any way we can reduce the amount of iterations? thanks again