2. CORE CONCEPT
Equation for an Arithmetic Sequence
Let an be the nth term of an arithmetic
sequence with first term a1 and common
difference d. The nth term is given by:
an = a1 + (n-1)d
3. YOU TRY!
Write an equation for the nth term of the
arithmetic sequence. Then find a25.
1.) 4, 5, 6, 7, ….
2.) 8, 16, 24, 32, …
3.) 1, 0, -1, -2,…
an = n + 3; 28
an = 8n ; 200
an = -n +2 ; -23
4. EXAMPLE 5 – WRITING REAL-LIFE
FUNCTIONS
Online bidding for a purse increases by $5 for each bid. After
the $60 initial bid.
�A. Write a function that represents the arithmetic sequence.
�B. Graph the function
�C. The winning bid is $105. How many bids were there?
5.
6. Online bidding for a purse increases by $5 for
each bid. After the $60 initial bid.
�B. Plot the ordered pairs.
7. EXAMPLE 5 – WRITING REAL-LIFE
FUNCTIONS
There were
10 bids.
8. A carnival charges $2 for each game after you pay a $5 entry fee..
A. Write a function
that represents the
arithmetic
sequence.
B. Graph the function
C. How many games can you play when you take $29 to the
carnival?
12 games