Arithmetic Sequences

Arithmetic Sequences

Lesson 2-6a & 2-6b Review

​f(n) = f(n-1)+d

​Recursive Formula

Multiple Choice

Write the RECURSIVE formula.

0, 3, 6, 9,12...

• f(n) = f(n-1)+3

• f(n) = f(n-1)-3

• f(n) = f(n-1)+6

• f(n) = f(n-1)-6

Multiple Choice

Write the RECURSIVE formula. 

-7, -5, -3, -1, 1...

• f(n) = f(n-1) -3

• f(n) = f(n-1) +3

• f(n) = f(n-1) +2

• f(n) = f(n-1) -2

Multiple Choice

Find the Recursive Formula of the following Arithmetic Series

5, 8, 11, 14, 17, ...

• f(n)=f(n-1)+4

• f(n)=f(n-1)-3

• f(n)=f(n-1)+5

• f(n)=f(n-1)+3

​f(n) = f(1)+d(n-1)

​Explicit Formula

Multiple Choice

Write the EXPLICIT formula.

-5, -8, -11, -14, -17,...

• f(n)= 5 + 3(n-1)

• f(n)= -5 - 3(n-1)

• f(n)= 5 - 3(n-1)

• f(n)= -5 + 3(n-1)

Multiple Choice

If the Explicit Formula of an Arithmetic sequence is: 

f(n) = 27-5(n-1)

What is the common difference?

• -5

• 27

• 5

• -27

Multiple Choice

Find the Explicit Formula of the following Arithmetic Series

5, 8, 11, 14, 17...

• f(n) =-5-3(n-1)

• f(n) =-5+3(n-1)

• f(n) =5-3(n-1)

• f(n) =5+3(n-1)

Multiple Choice

Find the next three terms of the following arithmetic sequence.

-7, -5, -3,...

• -2, 2, 4

• -1, 1, 3

• 1, -3, -5

• -2, -3, -4

Multiple Choice

If the Explicit Formula of an Arithmetic sequence is: 

f(n) = 30-5(n-1)

Find its 25th term.

• -70

• -85

• -90

• -100

Multiple Choice

If the Explicit Formula of an Arithmetic sequence is: 

f(n) = 27-5(n-1)

Find its 50th term.

• -218

• -300

• -215

• 218

Multiple Choice

The common difference of an arithmetic sequence is -8 and its first term is 52.  What is the 3rd term of this sequence?

• 28

• 36

• 60

• -36

Multiple Choice

The EXPLICIT formula of the sequence 17, 9, 1, -7, -15, is

f(n) = 17-8(n-1)

Find f(21).

• -143

• -124

• 143

• 21