# Euler’s method in Excel to simulate simple differential equation models

It is shown how to implement Euler’s method in Excel to approximately solve an initial‐value problem (IVP). Excel 2007 was used.

As example we take a model of an irreversible molecular decay reaction:

Which, according to the law of mass action, can be described with the following (linear, first order) differential equation:

See pdf.

**Exercises**

1. Change the initial condition from 5 to *y*(0) = 2. Observe that the simulation is updated automatically

2. Increase the rate constant *k* to 10 and run the simulation with a timestep of 1. Subsequently, change the timestep such that an accurate simulation result is obtained.

List of files: