standard_description: Generate two numerical patterns using two given rules. Identify apparent relationships between corresponding terms. Form ordered pairs consisting of corresponding terms from the two patterns, and graph the ordered pairs on a coordinate plane. For example, given the rule “Add 3” and the starting number 0, and given the rule “Add 6” and the starting number 0, generate terms in the resulting sequences, and observe that the terms in one sequence are twice the corresponding terms in the other sequence. Explain informally why this is so.
problem_activity: Problem 1
Consider the sequence below.
$${1, \space1,\space 2,\space 3,\space 5,\space 8,\space 13,\space 21, \space34, …}$$
a.   Describe the pattern that you notice. How is each next term determined?
b.   This pattern is famously called the Fibonacci sequence. Write a recursive formula to represent the Fibonacci sequence. Write a formula in sequence notation using
$${a_n}$$
and in formula notation using
$${f(n)}$$
.
c.   If
$${a_{15}=610}$$
and
$${a_{16}=987}$$
, what are the values of
$${a_{17}}$$
and
$${a_{14}}$$
?
Problem 2
For each sequence below, write a recursive formula, in both sequence notation and function notation, to represent the sequence.
a.
$${18,\space 13,\space 8,\space 3,\space -2,\space …}$$
b.
$${4,\space 12,\space 36,\space 108,\space 324,\space …}$$
Problem 3
A sequence is given by an explicit formula, as shown below, where
$$n$$
represents the term number.
$$a_n=4n-1$$
for
$$n\geq1$$
a.   Write the first five terms in the sequence.
b.   Write a recursive formula to represent the sequence.


aligns: no