Sequences

1. Write down the next three terms in each sequence:

a -8, -11, -14, -17, ...

• -20, -23, -26

• -19, -21, -23

• -24, -34, -44, -54

• -21, -25, -30

1. Write down the next three terms in each sequence:

b 9, 16, 25, 36, …

• 49, 64, 81

• 53, 66, 79

• 40, 50, 60

• 51, 64, 76

1. Write down the next three terms in each sequence:

c ½, ⅔, ¾, ⅘, ...

• 5/6 , 6/7, 7/8

• 4/3, 8/9, 5/4

• 7/9, 9/13, 12/5

• 1/2, 2/3, 4/6

2. For the following sequence, find an expression for the general term and state whether the sequence is arithmetic, geometric or neither:
a 10, 50, 250, 1250

•  $u_n=10(5)^{n-1}$  geometric

•  $u_n=10+(5)^{n-1}$  arithmetic

•  $u_n=10(2)^n$  geometric

•  $u_n=10+(1)^n$  arithmetic

2. For the following sequence, find an expression for the general term and state whether the sequence is arithmetic, geometric or neither:

b 41, 35, 29, 23, ...

• $u_n=-6n+47$ arithmetic

• $u_n=41^{n-1}$ geometric

• $u_n=5n+21$ arithmetic

• $u_n=-10^{n+1}$ geometric

3. For the the following real-life situation, give the general term and state whether the sequence is arithmetic, geometric or neither.

a Ahmad deposits $100 in a savings account every month. After the first month, the balance is $ 100; after the second month, the balance is $200; and so on.

• $u_n=100n$ arithmetic

• $u_n=100^n$ geometric

• $u_n=10\left(10^n\right)$ geometric

• $u_n=100+10^n$ arithmetic