You are Here: Home >< Maths

# Simple question ... Numerical methods watch

1. So far, numerical methods is fine, just one question, about the secant/false position methods.

I find these two methods some what equilant to each other, but after doing things like fixed point iteration, to create a table of values for the converging values after each iteration to the roots of a particular polynomial, I find the false position and secant method aomewhat harder.

Harder as in, in the fixed point iteration method, I just use my ANS button in my calculator after each iteration, to use the previous answer as part of x, to create a table of the converging roots.
But when doing the false position method, the previous values of two points have to be b and a have to be entered into the formula:

af(b)-bf(a) / f(b)-f(a)

where f(b) and f(a) are the y-values of the function when x=a and x=b
this will give values x(1), x(2), x(3) etc...
which converge to the root of f(x)

But after about 3 or so iterations, I have very long numbers, and I can't use the ANS key in my calculator anymore because theres two values a and b which have to be noted from previous iteration, and also to do another iteration, I have to work out f(a) and f(b) etc..

I find this method so tedious, to enter values such as a=1,.37474393,
b=2.48485484 etc, to find the root inbetween a and b.
Has anybody actually got a practical method of doing the false position method, with simplicity, it just becomes to tedious and time-wasting.

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: July 1, 2005
Today on TSR

### Edexcel C3 Maths Unofficial Markscheme

Find out how you've done here

### 1,122

students online now

Exam discussions

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams