Page 126 - IM_Algebra2_FL Print Sample.pdf

6. Find . Which version of the de nition of is easier to use?
Student Response
1. 2. 3. 4. 5.
6.
There are 16 more small squares. for
See table. Neither.
Sample response: I prefer the recursive de nition, because I already know , and .
Sample response: I prefer the formula, because nding using the recursive de nition will take a very long time.
stage,
number of small squares,
0
0
1
1
2
5
3
14
4
30
5
55
6
91
7
140
Activity Synthesis
Focus the discussion on the last two questions. Ask a student to demonstrate how they found
and another to demonstrate how they found If any students used the recursive de nition to nd it is useful to contrast their work side by side with a student who used the closed formula for to nd . Tell students that in the next lesson, they will learn how to create formulas like these that allow them to nd the value of any term without having to nd all of the terms leading up to it.
6.3 Info Gap: Ways To Represent A Sequence
20 minutes
Unit 1 Lesson 6: Representing Sequences 61