Area under curves and Limit of a sequence,

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Discussion Overview

The discussion revolves around the calculation of the area under curves and the limits of sequences, specifically focusing on techniques for evaluating integrals and limits. Participants seek assistance with examples and explore various methods for solving these problems.

Discussion Character

  • Homework-related, Mathematical reasoning

Main Points Raised

  • Francesco requests help with solving problems related to area under curves and limits, expressing urgency due to time constraints.
  • One participant suggests that the area can be computed using the integral \(\int_{0}^2(-(x-2)^3+2)-(x^2-2)\,dx\).
  • Another participant mentions that limits of the form \(\lim_{n\to\infty}f(n)^{g(n)}\) can be easier to compute using the representation \(e^{g(n)\ln(f(n))}\) and asks for known methods to find limits.
  • Participants propose methods such as substitution, expansion, and l'Hospital's rule for finding limits, with one suggesting that expanding \(\ln(1+x)\) may be the easiest approach.
  • It is noted that l'Hospital's rule requires the function to be represented as a ratio of two functions that both tend to zero or infinity.

Areas of Agreement / Disagreement

Participants express various methods for solving the problems, but there is no consensus on a single approach or solution. The discussion remains open with multiple techniques being proposed.

Contextual Notes

Some methods mentioned depend on specific conditions, such as the form of the functions involved in limits and the requirements for applying l'Hospital's rule. The discussion does not resolve which method is preferable or most effective.

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Hello, I am looking for an help about this, I have very short time to do many of them and those are an example, could someone show me one solution or explain me how to do it?
Thank you if you can help me, I really appreciate.
Francesco.

 
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Judging by the picture (clickable)

[GRAPH]5wib4rocqz[/GRAPH]

the area is
\[
\int_{0}^2(-(x-2)^3+2)-(x^2-2)\,dx
\]

Limits of the form $\lim_{n\to\infty}f(n)^{g(n)}$ are usually easier to compute when the function is represented as $e^{g(n)\ln(f(n))}$. Which ways of finding limits do you know?
 
Evgeny.Makarov said:
Judging by the picture (clickable)

[GRAPH]5wib4rocqz[/GRAPH]

the area is
\[
\int_{0}^2(-(x-2)^3+2)-(x^2-2)\,dx
\]

Limits of the form $\lim_{n\to\infty}f(n)^{g(n)}$ are usually easier to compute when the function is represented as $e^{g(n)\ln(f(n))}$. Which ways of finding limits do you know?

By substitution, or expanding, or Hospital rule i suppose.

Thank you
 
namerequired said:
By substitution, or expanding, or Hospital rule i suppose.
I think, the easiest way is to expand $\ln(1+x)$ as $x+o(x)$, but l'Hospital's rule works too. Recall that to apply the rule you need to represent the function as a ratio of two functions that tend both to zero or both to infinity.
 

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