nth term

nth term is a formula to work out a sequence of numbers

To work out the nth term:

9  12  15  18  21

1. Work out the difference between each of these numbers
This is the 'nth' part

In this case, the difference is 3, so we write '3n'

2. We take the difference of the numbers off the first number given

In this case 9 - 3 = 6

3. Put them together, 3n+6

You could also be asked to work out what a certain number of a sequence given will be.

For example, Work out the 5th sequence of:

6n + 2

Simply, replace the 'n' with the number in the question

In this case, (6 x 5) + 2  = 32

Lastly, you could be asked to give the first 5 or so terms of a sequence.

For example, work out the first 5 terms of:

6n + 2

1. (6 x 1) + 2   = 8

2. (6 x 2) + 2   = 14

3. (6 x 3) + 2   = 20

4. (6 x 4) + 2   = 26

5. (6 x 5) + 2   = 32