Taylor Polynomials: Order 4 for ln(1+x), Derivative Patterns, and Error Analysis

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Homework Help Overview

The discussion revolves around finding the Taylor polynomial of order 4 for the function ln(1+x) centered at 0, exploring derivative patterns, and analyzing the error associated with the polynomial approximation. Participants are also considering how to determine the necessary order of the polynomial to achieve a specific error threshold when approximating ln(1.3).

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss differentiating ln(1+x) to identify a pattern in the derivatives and how these relate to constructing the Taylor polynomial. There is also a focus on the remainder term and its implications for error analysis. Questions arise regarding the assumptions made in the error estimation and the need for showing work in the problem-solving process.

Discussion Status

The discussion is ongoing, with some participants providing their attempts at the solution while others emphasize the importance of showing work and relevant formulas. There is a mix of contributions, with some participants seeking clarification and others offering insights into the derivative patterns and remainder terms.

Contextual Notes

One participant notes a lack of access to university resources, which may affect their ability to engage fully with the problem. There is also an emphasis on the need to adhere to homework guidelines, which may impose constraints on the type of assistance that can be provided.

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Homework Statement


(a) Give Taylor Polynomal of order 4 for ln(1+x) about 0.
(b) Write down Tn(x) of order n by looking at patterns in derivatives in part (a), where n is a positive integer.
(c) Write down the remainder term for the poly. in (b)
(d) How large must n be to ensure Tn gives a value of ln(1.3) which has an error less than 0.0002

Question 2 part d

Homework Equations


The Attempt at a Solution


Okay so we have that the taylor poly is Tn(x) = ∑[f'(a)(x-a)^n]/n! where f' is the nth derivative
And the remainder is Rn(x) = f'(c)(x-a)^(n+1)/(n+1)! where f' is the n+1 th derivative and c lies between x and a
For part a I differentiated ln(1+x) a few times and got a pattern... the values I got at x=0 were 0, 1, -1, 2, -6, 25, -120.
and I got T4 = x - x^2 /2 + x^3 /3 -x^4 /4
b. I got the highest term as (-1)^(n+1) x^n /n
c. I got the remainder term to be (-1)^n (x^(n+1)/(1+c)^(n+1)*(n+1))
d. I got an answer of n=4999 using the approximation that abs(Rn) is always less than abs(1/(n+1))
 
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I am afraid I don't have a log in for the university of Sydney.
 
Sorry about that
 
You want to be taken through the entire exercise, which is fine. However it is not fine to request that without showing your work. So let's start with that, show your work for a b c, write down the formulae you think are relevant. Like Taylor's theorem the definition of the remainder etc.
 
Updated
 

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