body{margin:0;} noscript{z-index: 10000; position: fixed; display: block; height: 100%; width: 100%; background: #fff;} noscript .fa{font-size: 40px; display:block; color: #daa520;} noscript div{margin-top: 6%; padding-left: 20px; padding-right: 20px; text-align: center;} ! You must have JavaScript enabled to use this site.

Pearson Algebra 1 Common Core, 2011

PA

Pearson Algebra 1 Common Core, 2011 View details

7. Arithmetic Sequences

Continue to next subchapter

Exercise 5 Page 278

The common difference of the arithmetic sequence in this case is $- 2 .$

Recursive Formula: $A (n) = A (n - 1) - 2, A (1) = 9$
Explicit Formula: $A (n) = 9 - 2 (n - 1)$

Practice makes perfect

In order to write the formulas for the given arithmetic sequence, we first need to find the common difference. We can do this by subtracting the first term of the sequence from the second term.

a_{2} - a_{1} = d \Rightarrow 7 - 9 = - 2

The common difference is

- 2 .

Let's now find the recursive formula and the explicit formula one at a time.

Recursive Formula

To write the recursive formula, we will use the general form for a recursive formula of an arithmetic sequence.

A shortcut to better grades

Download the app and create a free account to view full content

Subchapter links

Lesson Check p.278

Practice and Problem-Solving Exercises p.279-281

Standardized Test Prep p.281

Mixed Review p.281