Week 2 – Infinite Geometric Sequences

Our last lesson this week was on infinite geometric sequences.

We learnt about diverging and converging graphs

The above graph is an example of a diverging graph because it keeps getting bigger. It has no sum r>1, r<-1

The above graph is an example of a converging graph because all the points will add up to a certain a number- converges to a certain number. It will have an actual sum. 0<r<1

 

Infinte Geometric sequences have their own formula.

So lets say =2 and = 4 and you needed to find the common ratio you would do the following.

  Here you would cross multiply

4-4r=2

-4r=-2

r=0.5