Simulaneous Non Linear Equation Solver


This is a template that allows the use of the Solver tool in Excel to solve a set of coupled non-linear equations. It makes use of the Solver add-in.


.xls file (18 KB) (This file contains the example described below.)

How to use

The use of this template is best illustrated by an example. Let us solve the following coupled  simultaneous non-linear equations:

x = sin(y) and y = cos(x)

Initial guesses for the variables are entered under 'Variables' in column A and the equations are keyed into column B. The equations must be in the form f(variables) = 0, hence we key in the equations as:

x - sin(y) and y - cos(x)

The figure below shows the setup.


Now go to Tools, choose Solver and set it up to target cell C4 to 0 as shown in the figure below.


Solver will try to find a solution to the equations. In this case, it comes up with the following solution:

x = 0.6951 radians (39.8 degrees), y = 0.7684 radians (44.0 degrees)


Also See:

Non-linear Equation Solver

Linear Equation Solver

First order ODE Solver