LBS290F                                                      Fall 1991

                     ASSIGNMENT 20 - ALGEBRA

Due Date: 11:59 PM 11/25/91

The purpose of this program is to use bisection to find the roots of 
a function to within an epsilon of 0.00001.  Use double precision
variables.  The root falls somewhere between 1.0 and 100.0.

The book shows a technique called recursion to find the roots.  You may 
use recursion if you like.  You can do bisection without recursion using
the following pseudo-code:

  Set left and right to the area to be searched
  Make sure the root is really between left and right
  for(i=0; i<20; i++) {
    check to see if f(left) or f(right) is zero - if so, set root and quit
    compute root guess to be halfway between left and right
    check to see if left and right are closer than epsilon.  If so quit

    if the real root is between left and root guess, set right to the 
     root guess
    if the real root is between right and root guess, set left to the 
     root guess
  }
  print root

A function will be provided for you to use.  To use the function type:

  $ cc assn20.c /usr/usrs/crs/f.o
  $ a.out

The header for function f is as follows:

  double f(x)
   double x;
  {
  }