Why is the coefficient -2 instead of -2/3 in the improper integral solution?

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Homework Help Overview

The discussion revolves around an improper integral involving the expression \(\int (x-2)^{-3/2}dx\). Participants are examining a specific step in the integration process where a coefficient appears in the result.

Discussion Character

  • Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to understand why the coefficient of -2 arises after integrating the expression, questioning whether it should instead be -2/3. Another participant suggests taking the derivative of the result to clarify the coefficient.

Discussion Status

Participants are engaging in a constructive dialogue, with one offering a suggestion to verify the coefficient through differentiation. There is an acknowledgment of common mistakes in the integration process, indicating a supportive atmosphere for learning.

Contextual Notes

No specific constraints or missing information have been noted in the discussion.

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Homework Statement


[itex]\int[/itex] (x-2)-3/2dx

Homework Equations


[itex]\int[/itex]f(x)dx from 0 to ∞ = lim (t[itex]\rightarrow[/itex]∞) [itex]\int[/itex]f(x)dx from 0 to t

The Attempt at a Solution


I have the solution from the solution manual, but I'm just not sure on one of the steps, after you substitute u=(x-2) and du=dx, then integrate u-3/2, but they say that the result to this step is lim(t[itex]\rightarrow[/itex]∞) -2(x-2)-1/2, that is when they integrate u-3/2 they are getting a -2 coefficient, shouldn't it be a -2/3
 
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Try taking the derivative of the answer to see why it is a -2.

##\int x^n dx = \frac{1}{n+1} x^{n+1}, n \neq -1##
 
I'm ummm, I'm face palming right now, thanks.
 
It's okay. Everybody has done something similar at one point or another!
 

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