How Do I Solve This Integral with Completing the Square and Long Division?

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Hello, can someone help me solve this integral? I think I need to complete the square...I've tried many other things but I don't know what else to use :confused:

integral.jpg


and

integral2.jpg


With the last one I did long division and I ended up with: x + x/ (x - 1)...so I can easily solve the first integral of X but now I can't solve the other part... :(
 
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Try using latex, it might be a while before we can view your image.
 


I posted the image differently :)
 


U-sub is the easiest on the first one, u-sub and factor actually...

U-sub the second one too
 


Fiorella said:
Hello, can someone help me solve this integral? I think I need to complete the square...I've tried many other things but I don't know what else to use :confused:

integral.jpg


and

integral2.jpg


With the last one I did long division and I ended up with: x + x/ (x - 1)...so I can easily solve the first integral of X but now I can't solve the other part... :(

you could rewrite

\frac{x}{(x-1)}

as

1+\frac{1}{x-1}

if that is any easier for you.
 
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Fiorella said:
Hello, can someone help me solve this integral? I think I need to complete the square...I've tried many other things but I don't know what else to use :confused:

integral.jpg
Not "complete the square", the denominator is a cube, not a square! The substitution
u= -x3+ 9x+ 1 works nicely.

and

integral2.jpg


With the last one I did long division and I ended up with: x + x/ (x - 1)...so I can easily solve the first integral of X but now I can't solve the other part... :(
You need to review your long division! x2 divided by x- 1 is x+ 1+ 1/(x-1).
 


Thank you so much everybody :)
 
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