How to Simplify Integration by Parts for a Complex Expression?

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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.