Textbook not clear explain this question(s)

  • Thread starter Thread starter viet_jon
  • Start date Start date
  • Tags Tags
    Explain Textbook
Click For Summary

Homework Help Overview

The discussion revolves around understanding limits in calculus, specifically the limits of sequences as n approaches infinity. The original poster presents two questions from their textbook regarding the existence of limits and the behavior of sequences.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the limit of the expression (n+1)/(n^2+1) and question how it approaches zero. There are attempts to manipulate the expression by dividing the numerator and denominator by n or n^2 to analyze the limit.

Discussion Status

Participants are actively engaging with the questions, exploring various approaches to determine the limits. Some have provided guidance on how to manipulate the expressions to find the limits, while others express confusion about the reasoning behind the limits approaching zero.

Contextual Notes

The original poster indicates they are taking an introductory calculus class and seeks clarification on the questions rather than direct answers. There is a mention of textbook constraints and the nature of the questions being potentially straightforward for more experienced participants.

viet_jon
Messages
131
Reaction score
0
[SOLVED] Textbook not clear... please help explain this question(s)...

Question 1.

Homework Statement



State whether the limit exists for (Limit as x aproaches infinity ==> (n+1)/(n+1)

and give the value of it if it does exist. Graph the first 5 terms of each sequence.

The Attempt at a Solution

if you use any number for "n", numerator divided by denominator would equal 1.


Question 2:

Homework Statement


The sequence a1, a2, a3 ... has the following possible nth terms. For the case given below try various large values for n and guess the limit. Confirm that guess by manipulating the general term an.

a(n) = (n+1) / (n^2+1)I'm taking a intro Calc class, so this is probably easy stuff for you guys, that's why I lumped both questions into one thread. Anhow, I'm not looking for an answer since it's in my book, I just want to know what the question is asking for.
 
Physics news on Phys.org
and... where's that thread that explains how to use syntax.edit: nm, I just found it...latex not syntax lol
 
So what's your question? Did you follow the suggestion and substitute various values of n? What's your guess of the limit?
 
question 1: limit equals 1?
 
question 2:


answer:

an = n + 1 / n^2 + 1

possible answers: 11/101, 101/10001, 1001/1000001 appears to have limit of zero?


but how does it have limit of zero?
 
Yep. Can you prove it? Divide numerator and denominator by n.
 
viet_jon said:
question 2:


answer:

an = n + 1 / n^2 + 1

possible answers: 11/101, 101/10001, 1001/1000001 appears to have limit of zero?


but how does it have limit of zero?

Same answer, yes. Can you prove it? Divide numerator and denominator by n^2.
 
oh wait...question 2's answer is from the book, not mine.

I attempted it the same way.....exceptwhat I don't understand is how it has a limit of zero?
 
Ok, divide numerator and denominator of 2) by n^2. This gives you (1/n+1/n^2)/(1+1/n^2), right? What's the limit of 1/n and 1/n^2?
 
  • #10
wait...

the question is (n + 1) / (n^2 +1)

so divide num/denom by n^2 it should be(n/n^2) + (1/n^2) / (n^2/n^2) + (1/n^2) right?then it goes

(1/n) + (1/n^2) / 1 + (1/n^2)

then it goes, which is the step I don't understand...(0+0) / (1 + 0) = 0/1 = 0where are all these zero's coming from?
 
  • #11
The limit of 1/n as n goes to infinity is zero. Likewise for 1/n^2. The numerator is 1 and the denominator gets larger and larger.
 

Similar threads

  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 5 ·
Replies
5
Views
1K