Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 12: Q 95. (page 1184)

Find the twentieth term of a sequence where the fifth term is −4 and the common difference is −2. Give the formula for the general term.

Short Answer

Expert verified

The twentieth term is -34 and the general term isan=−2n+6

Step by step solution

01

Step 1. Given Informaation. 

The fifth term is −4 and the common difference is −2.

02

Step 2. Find the first term by using the arithmetic formula. 

Substitute 5 for n,-2 for d, and the fifth term is -4, in the formula an=a1+n−1d.

a5=a1+5−1−2−4=a1−8a1=4

03

Step 3. Find the twentieth term.

Use the first term and the common difference to find the twentieth term.

a20=4+20−1−2=4−38=-34

04

Step 4. Find the general terms.

To find the general terms, substitute the first term 4 and the common difference -2 in the formula.

an=4+n−1−2=4−2n+2=−2n+6

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Write the first five terms of the sequence whose general term isan=2n!.

Write the first five terms of the sequence where the first term is 7 and the common ratio is r=-3.

Write the first five terms of the sequence where the first term is 6and the common ratio is r=-4.

Write the first five terms of the sequence whose general term is an=3n−4

In the following exercises, evaluate.

(a) 81 (b) 1010 (c) 60 (d)93
See all solutions

Recommended explanations on Math Textbooks

Probability and Statistics

Read Explanation

Logic and Functions

Read Explanation

Calculus

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Pure Maths

Read Explanation

Statistics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free