Sequences and progressions

In this section we’ll take a look at sequences and progressions.

We begin to come to terms with some of the more sophisticated aspects of sequences the moment we progress from counting by 1s to counting by 2s, 5s or 10s.  We have already seen a number of sequences when looking for patterns in problem solving, and in Topic 3 we looked at the language around sequential information (e.g. plots with respect to time).  Here we focus on two special types of sequences, ‘arithmetic progressions’ and ‘geometric progressions’, which help us to understand general trends of growth or decay – linear and exponential respectively.

Learning outcomes

• Solve problems using arithmetic and geometric progressions.