What do I need to know about modelling with sequences and series?
Many real-life situations can be modelled using sequences and series
If a quantity is changing repeatedly by having a fixed amount?added?to or?subtracted?from it then the use of?arithmetic sequences?and?arithmetic series?is appropriate
If a quantity is changing repeatedly by a fixed?percentage,?or by being?multiplied?repeatedly by a fixed amount, then the use of?geometric sequences?and?geometric series?is appropriate
Exam Tip
Remember, an exam question won't always tell you to use sequence and series methods, so you've got to be able to spot 'hidden' sequence and series questions.
To help you do this, be suspicious of questions about savings accounts, salaries, sales commissions, profits and the like – these are often sequence and series questions in disguise!