1. Maths Unit 8 – Sequences Picture sequences Number sequences
Sequences can be in the form of patterns or numbers
Here is a pattern sequence:
To draw the next pattern you need to spot what is happening from one pattern to the other. In this sequence 3 sticks are being added each time.
Here is a sequence;
In this sequence, 5 is added to the previous term to create the next number in the sequence. The pattern is infinite.
Using the nth term
You can use the nth term to find a specific number in a sequence.
To find the 8th term of a sequence which has a nth term of 6n – 2 you need to do some substitution
Step 1 – Replace n with the term number; in this case 8
So, 6 x 8 - 2
Step 2 – complete the calculation
So, 6 x 8 – 2 = 46
The 8th term of the sequence is 46
Finding the nth term
Here is a sequence. 1, 4, 7, 10. The nth term is 3n-2.
To find the nth term you start by finding the common difference between terms. The picture demonstrate the rest of the method to find the nth term.
Key words and definitions
Term – a single number or variable or numbers and variables multiplied together
Substitution – replacing letters with a given number
Sequence – a string of objects which follow a particular pattern. These can be pictures or numbers.
Pattern – when a picture or sets of numbers are in a specified sequence
nth term – an expression which will allow you to calculate a term that is in a particular position