Solution to Incorrect Homework Equation

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Homework Help Overview

The discussion revolves around a calculus problem involving the arc length formula, specifically the integral for calculating the length of a curve defined by a function. Participants are examining the setup of the integral and the limits of integration.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the setup of the integral and question the limits of integration, particularly the use of the number 7 and the interval notation. There is confusion regarding the correct bounds for the integral and the implications of the inequality presented.

Discussion Status

Some participants have provided clarifications regarding the limits of integration and the interpretation of the function. There is a mix of attempts to resolve the misunderstanding about the interval and the correct application of the arc length formula. While some have indicated they found the correct answer, there is no explicit consensus on the interpretation of the setup.

Contextual Notes

Participants are working under the constraints of a homework assignment, which may limit the information they can share or the methods they can use. There is an ongoing discussion about the correct interpretation of the problem's parameters.

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Homework Statement



so I did

Homework Equations



s=∫ba√(1+[f'(x)]2dx

The Attempt at a Solution


y=2/3x3/2+7
y'=x1/2 0≤x≤1
=∫6√(1+(x1/2)2)dx
=[2/3(1+x)3/2]7

my answer came out wrong
 

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chapsticks said:

Homework Statement



so I did

Homework Equations



s=∫ba√(1+[f'(x)]2dx

The Attempt at a Solution


y=2/3x3/2+7
y'=x1/2 0≤x≤1
Why do you have this inequality?
chapsticks said:
=∫6√(1+(x1/2)2)dx
=[2/3(1+x)3/2]7

my answer came out wrong
What is that 7 doing?
 
I saw it in an example for the inequality.. The 7 is for the a & b part I don't know how to place the 0 on the bottom.
 
chapsticks said:
I saw it in an example for the inequality.. The 7 is for the a & b part I don't know how to place the 0 on the bottom.
Your inequality is saying that the interval is [0, 1]. It's actually [0, 6].

Here's how your integral looks using LaTeX.
[tex]\int_0^6 \sqrt{1+x}~dx[/tex]

Here's how to write that integral in LaTeX.

[ tex]\int_0^6 \sqrt{1+x}~dx[ /tex]

(The extra spaces in the tex and /tex tags prevent the browser from rendering the code inside.)

Here's the antiderivative with limits of integration shown.
[tex]\left. \frac{2}{3}(1 + x)^{3/2}\right|_0^6[/tex]

The LaTeX for that.
[ tex]\left. \frac{2}{3}(1 + x)^{3/2}\right|_0^6[ /tex]
 
I got it correct :))
 

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Good to know. That's what I got, too.
 

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