## 5.How to calculate faster? - a discovery of logarithms.

• 1. How to calculate faster?    - a short story about discovery of logarithms.

Especially multiplication was difficult to make it faster - it brought a discovery of logarithms. Thanks to charts invented by Napier multiplication could be replaced by addition. It was effective especially for big numbers.

2. First steps
- Calculate a few examples of powers and roots.
- Provide a few examples of equations and let students guess the value of the exponent x. - Definition of logarithm. Calculate a few simple examples.

3. Introduction to the properties of  logarithms:
- Logarithm of a power,
- Logarithm of a product,
- Logarithm of a ratio,
- Changing the base of a logarithm.
Solving sample exercises. 4. Examples of  the practical use of  logarithms.
5 Homework:

Prepare a quiz on Kahoot platform to play between teams

First version of that lesson which took place in Polish school  a month before the meeting in Swarzędz it shown below

Here you can find presentations used during the lesson