erfen1.java

一个数值方法的课程设计

import java.io.*;
public class erfen1
{
	
	public static void main(String args[])
	{
		double a=1;
		double b=2;
	 	double x=0;
		double sum=0;
		System.out.print("请输入你要精度");
		try{
		
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		double T=Double.parseDouble(s);
		while((b-a)>T)
		{
			x=(a+b)/2;
		 	sum=x*x-x-1;
			if(sum>0)
			{
				b=x;	
			
			}
			else
			{
				a=x;		
			}
			
		}
		System.out.println("the result is  "+x);
		}catch(IOException e){}
	}


}