A geometric progression could be defined as a sequence of numbers where the quotient (or common ratio) of any two consecutive terms is always the same.

Therefore, each term is obtained by multiplying the preceding term by a constant multiple (
common ratio).

4.- In this window you can form geometric progressions by just indicating the first term and the common ratio.

5.- Form five progression. Make sure that the first term is different in each example and that the common ratio is positive and greater than 1 in some cases, positive but less than 1 in others and negative in others.

6.- Write down the first five terms and the 10th, 20th and 50th term in each sequence in your exercise book.

You can change the value of n with the arrows or by writing in the new value and pressing the Enter key.

7.- Choose one of your progressions and try to find a formula which allows you to obtain any term by knowing its position in the sequence (n).

an =

8.- Now try to do the same for the other four progressions.


  Juan Madrigal Muga
Spanish Ministry of Education. Year 2002

Licencia de Creative Commons
Except where otherwise noted, this work is licensed under a Creative Common License