The document provides notes from a math lesson on sequences and formulas for generating the terms of sequences. It includes examples of common sequences like triangular numbers and their formulas. It also provides practice problems for students to find specific terms in sequences based on their position or using given formulas. The lesson explains that sequences can often be defined by a rule or formula relating the term number to its value.

1. Lesson 73.notebook
March 06, 2014
Assignment:
1-->Set 73 (odds) - Due Tomorrow [3/7]

2. Lesson 73.notebook
March 06, 2014
Lesson 73 Warm-Up:
1) 38% of the students went to the Cards game. If there were 150
students in all, how many did not go to the Cards game?
2) Graph: y = 2x - 2
or why not?
3) Graph: y = 1/2x
why not?
Does the graph show direct variation? Why
Does the graph show direct variation? Why or
4)
What is the tax on a $85.97 purchase if the rate is 8%?
5)
Solve:
2(x + 7) - 4 = 24
[show all steps!]

3. Lesson 73.notebook
March 06, 2014
Lesson 73:
fyi...when we have a sequence of numbers, we can write the
"rule" as a formula.
number of term (n)
1
2
3
4
5
value of term (a)
3
6
9
12
15
The rule-->multiply by 3
The formula--> an = 3n
So...to find the 7th term, plug in 7 for both "n's"

4. Lesson 73.notebook
March 06, 2014
Some sequences have special names...
1, 3, 6, 10, 15, ...
This is called triangular numbers because...
The formula for this sequence is: an = n(n + 1)
2
100th term-->

5. Lesson 73.notebook
March 06, 2014
Lesson 73 Examples:
A) What is the 7th term in this sequence:
1, 4, 9, 16, ...
B) Using the formula an = 5n - 2 what would be the 10th term?
C) Which formula below generates the terms of this sequence?
0, 3, 8, 15
A. an = n - 1
B. an = 2n - 1
C. an = n2 - 1

6. Lesson 73.notebook
D) What are the first 4 terms in the sequence generated by
the formula: an = n2 + 2n + 1
E) What is the 20th triangular number?
F) Find the 20th term for the following sequence:
an = 2n - 3
March 06, 2014