Page 22 - Mathematics Coursebook

2.1 Generating sequences (1)

3 Copy these finite sequences and fill in the missing terms.
a 2, 5, , 11, ,17, 20 b 5, 11, 17, , , 35,
c 26, 23, , , 14, , 8 d 90, 82, , 66, , 50,

e 8, , , 32, 40, , f , , 28, 23, , , 8

4 Write down whether each of these sequences is finite or infinite.

a 4, 6, 8, 10, … b 3, 5, 7, 9, 11, 13, 15
c 85, 75, 65, 55, 45, 35 d 100, 97, 94, 91, 88, …
5 Copy this table.

First term Sequence Term-to-term rule
3 11, 14, 17, 20, …, … Subtract 2

80 17, 15, 13, 11, …, … Divide by 2
64 3, 6, 12, 24, …, … Multiply by 5 then add 1

11 80, 40, 20, 10, …, … Multiply by 2
17 1, 6, 31, 156, …, … Divide by 2 then add 4

1 64, 36, 22, 15, …, … Add 3

Draw a line connecting the sequence on the le# with the $rst term in the middle, then with the

term-to-term rule on the right. "e $rst one has been done for you.
6 Shen and Zalika are looking at this number sequence:
4, 8, 20, 56, 164, …, …
I think the term-to-term rule is: ‘Add 4.’

I think the term-to-term rule is: ‘Multiply by 2.’

Is either of them correct? Explain your answer.
Is either of them correct? Explain your answer.

7 Ryker is trying to solve this problem. The second term of a sequence is 13.
Work out the answer to the problem. The term-to-term rule is: ‘Multiply
Explain how you solved it. by 2 then subtract 3.’
What is the first term of the sequence?

The third term of a sequence is 48.
8 Arabella is trying to solve this problem. The term-to-term rule is: ‘Subtract 2
Work out the answer to the problem. then multiply by 3.’
Explain how you solved it. What is the first term of the sequence?

2 Sequences, expressions and formulae 21