/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 43 Use a spreadsheet to calculate t... [FREE SOLUTION] | 91Ó°ÊÓ

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Use a spreadsheet to calculate the specified term of each recursively defined sequence. If \(a_{n+1}=\frac{1}{4} a_{n}+1\) and \(a_{0}=0\), find \(a_{14}\).

Short Answer

Expert verified
The value of \(a_{14}\) is approximately 1.333.

Step by step solution

01

Initialize Parameters

Start by understanding that the first term, \(a_0\), is given as 0. The recursive formula we need to use is \(a_{n+1} = \frac{1}{4}a_n + 1\). Our goal is to find the 15th term, \(a_{14}\).
02

Set Up Spreadsheet

In your spreadsheet, label the first column as 'n' indicating the term number, and the second column as 'a_n' indicating the value of the sequence at that term. In the first row, input 0 for 'n' and 0 for 'a_0'.
03

Apply Recursive Formula in Spreadsheet

In the second row of your spreadsheet, for the 'n' column enter 1, and for the 'a_n' column enter the formula \(= \text{(cell containing } a_0 \text{)}/4 + 1\). This will calculate the next term, \(a_1\).
04

Fill Down Formula

Drag the formula from Step 3 down the 'a_n' column until you reach \(n=14\). Each cell in this column should reference the cell above it, applying \(a_{n+1} = \frac{1}{4}a_n + 1\).
05

Read the Result

Once all computations are complete, the cell at \(n=14\) will contain the value of \(a_{14}\), which is the term you need to find.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Spreadsheet Calculations
To effectively calculate recursively defined sequences and manage data, spreadsheets offer a powerful tool. They allow you to automate repetitive tasks, such as calculating sequence terms, by setting up a systematic approach with formulas. A spreadsheet is particularly useful when working with sequences because it lets you easily apply a formula to a range of cells and update terms with minimal manual effort.
  • Start by opening a spreadsheet software like Microsoft Excel or Google Sheets.
  • Label columns clearly to track terms and their values.
  • Input initial values and set cells to reference one another, enabling forward computation via formulas.
  • Use drag-and-fill techniques to automate the application of recursive formulas down columns.
Overall, using a spreadsheet not only enhances accuracy but also simplifies the computation of complex sequences. This ensures that even if you're calculating up to the 14th term or beyond, the process remains clear and manageable.
Sequence Terms
In sequences, each term presents a unique position and value within a list. A term in a sequence is typically represented by a subscript, such as \(a_n\), where \(n\) specifies the term's position.
The position tells you where the term appears, and the value is what you calculate or assign based on the sequence's rule. For instance, in the context of recursive sequences, you're provided with an initial term, which serves as a starting point for calculating subsequent terms according to a specific formula.
  • Begin with the initial term, such as \(a_0\) which might be provided, here it's 0.
  • Follow the recursive relationship to find later terms, such as \(a_1, a_2, ..., a_{14}\).
  • The formula allows each term to be calculated based on the previous term.
Understanding the position and value of each sequence term is crucial because it enables you to identify patterns or predict future values using consistent rules.
Recursive Formula Application
Recursive formulas define each term in a sequence based on one or more preceding terms. This ties the sequence together, creating a chain of calculations that depend on prior terms for determining subsequent values. In our given exercise, the recursive rule is \(a_{n+1} = \frac{1}{4}a_n + 1\).
When applying this:
  • Start with known values: Here, \(a_0 = 0\).
  • The formula specifies how to determine each subsequent term \(a_{n+1}\) based on \(a_n\).
  • For instance, \(a_1 = \frac{1}{4}a_0 + 1\) results in \(a_1 = 1\) since \(\frac{1}{4} imes 0 + 1 = 1\).
  • Each application of the formula is contingent on correctly computing the prior term.
This recursive application necessitates careful attention to detail; an error in one term can cascade through subsequent calculations.

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