## Unit 7 Section 4 : Formulae for General Terms
In the last section we learnt that we could use a formula which contains
For the sequences 5
n in the formula for the nth term of sequence.
Imagine we want to find a formula for the
We can see that the terms in this sequence go up by 4 each time, so The sequence generated by the formula 4 n is the four times table, but it isn't quite the sequence we want:
n sequence.
Hence, the general formula for the
## Example QuestionWork out the answer to each part of the question then click to see whether you are correct.
We want to find a general formula for the 5, 13, 21, 29, 37, ...
(a) What amount do the terms in the sequence go up by each time?
(b) What will definitely appear in the formula for the
(c) What sequence is generated by the general formula 8
(d) What adjustment needs to be made to the 8
(e) What is the general formula for the
## ExercisesWork out the answers to the questions below and fill in the boxes. Click on the button to find out whether you have answered correctly. If you are right then will appear and you should move on to the next question. If appears then your answer is wrong. Click on to clear your original answer and have another go. If you can't work out the right answer then click on to see the answer.
When answering questions with formulae, simplify your answer and use a lowercase n.
You have now completed Unit 7 Section 4
Produced by A.J. Reynolds April 2011 |