Tag Archives: Jenkins-Traub

Solving Quadratic, Cubic, Quartic and higher order equations; examples

Posted on 14/01/2014 by dougaj4

A previous post presented a spreadsheet with functions for solving cubic and quartic equations, and this has been extended with another function solving higher order polynomials.  The functions are actually very easy to use, but the documentation in the spreadsheets is quite brief, … Continue reading →

Posted in Arrays, Excel, Link to Python, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , , | 13 Comments

Polynomial Update

Posted on 30/10/2012 by dougaj4

Following a comment here: Solving cubic and quartic equations with Excel the Quartic and CubicC User Defined Functions (UDFs) have been amended to fix a problem occurring with some combinations of coefficients. The updated spreadsheet (including full open source code) can be … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | 12 Comments

Daily Download 19: Solving polynomials

Posted on 06/10/2012 by dougaj4

Today’s download provides analytic solutions to polynomial equations up to fourth order (that is quadratic, cubic and quartic equations) and an iterative method to solve equations of higher order.  All these functions are found in the download file: http://interactiveds.com.au/software/Polynomial.zip The … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , | 1 Comment

Linest, NPV, IRR and solving polynomials

Posted on 01/12/2011 by dougaj4

In a comment on Using LINEST for non-linear curve fitting Lori Miller posted a formula that found the coefficients fitting a cubic polynomial curve to a set of data, then solved the resulting equation to find the X value for a given … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 3 Comments

Evaluating higher order polynomials …

Posted on 17/01/2011 by dougaj4

… and a better solution for quadratics. Having written a better solver for high order polynomials, that raises a few other issues.  The error in the roots found by the RPolyJT was checked by simply substituting each root as the … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 4 Comments