In this worksheet, we will learn how to find the formula for the general term, Tn, of a sequence.
Example
Term no., n = 1 2 3 4 5
Term, Tn= 4 8 12 16 20
Common difference = +4 +4 +4 +4
It is clear, that Tn = 4n.
Also note that the difference between each term is 4.
Compare this sequence with the one below:
Term no., n = 1 2 3 4 5
Term, Tn= 7 11 15 19 23
Common difference = +4 +4 +4 +4
The common difference of +4 tells us that this sequence is "related" to the first one .
It begins Tn = 4n... and so is in the 4n "family".
Compare the two and you will see that each term is 3 more than that in the first sequence.
7 = 4 + 3
11 = 8 + 3
15 = 12 + 3
So Tn = 4n + 3
