# Newton's Polynomial Solver

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

This Demonstration shows Newton's method of finding approximate roots of an equation by using three slide rules, called *primary*, *secondary*, and *tertiary*. We can read directly with an *auxiliary primary* rule. We calculate the value of polynomial for , , and . If its value for is near , is approximately a root of the equation.

Contributed by: Izidor Hafner (October 2012)

Based on a note by: C. J. Sangwin

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

The slide rules are called primary, secondary, and tertiary. On the primary rule we read according identity . On the secondary rule we read according . The tertiary rule gives us , . The actual value of the polynomial at is , the signs being determined appropriately.

Reference

[1] C. J. Sangwin, "Newton's Polynomial Solver,"* Journal of the Oughtred Society*, 11(1), 2002. pp. 3–7. web.mat.bham.ac.uk/C.J.Sangwin/Sliderules/newtonpoly.pdf.

## Permanent Citation