How to Simplify Integration by Parts for a Complex Expression?

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Homework Help Overview

The discussion revolves around simplifying an integral using integration by parts, specifically for the expression involving the square root of x and polynomial division. The subject area is calculus, focusing on integration techniques.

Discussion Character

  • Exploratory, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore substitution methods and polynomial division to simplify the integral. Questions arise regarding the simplification of specific terms and the correctness of derived expressions.

Discussion Status

Some participants have provided guidance on using polynomial division and have shared their results. There is an ongoing exploration of the correctness of the derived expressions, but no explicit consensus has been reached.

Contextual Notes

The original poster's approach involves changing the limits of integration due to substitution, which may influence the discussion. There is also a focus on ensuring the accuracy of the integration steps taken.

Dell
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4[tex]\int[/tex]9[tex]\frac{1-\sqrt{x}}{\sqrt{x}+2}[/tex]

what i did:
t=[tex]\sqrt{x}[/tex]
x=t2
dx=x'dt=2tdt

now my integration is from 2-3 instead of 4-9

[tex]\int[/tex][tex]\frac{1-t}{t+2}[/tex]2tdt=2[tex]\int[/tex][tex]\frac{t-t<sup>2</sup>}{t+2}[/tex]dt

=2([tex]\int[/tex][tex]\frac{t}{t+2}[/tex]dt-[tex]\int[/tex][tex]\frac{t<sup>2</sup>}{t+2}[/tex]dt)

the 1st integral i can replace with[tex]\int[/tex]1-[tex]\frac{2}{t+2}[/tex]dt which is an immediate integral, but how do i simplify the second part??
 
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Just divide t+2 into t^2 using polynomial division. Actually, you might want to take a step by and divide t-t^2 by t+2.
 


i get t+3-[6/(t+2)]

so i get --->2[(t^2)/2]+3t-6ln|t+2|]
is this right??
 


Dell said:
i get t+3-[6/(t+2)]

so i get --->2[(t^2)/2]+3t-6ln|t+2|]
is this right??

Sure.
 

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