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!