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Re: Compute integral
Posted:
May 2, 2014 6:31 AM


On Friday, May 2, 2014 12:50:45 AM UTC4, coote...@gmail.com wrote: > Compute the integral from 0 to 1 of ln(1+x)/(1+x^2)dx. Hint: Use the substitution y+1=2/(x+1) > > > > I'm pretty sure I need to get this in the form of the integral of ln u du. So I use the substitution given and let u = 2/(x+1) but when I compute the derivative of this I get [(x+1)*0  2(1)]/(1+x)^2 = 2 /(1+x)^2 which does not equal 1/(1+x^2) like I need. I didnt get too far trying integration by parts but maybe that is the way to go? I doubt it because of the hint so pretty sure I am just missing something getting it in the form of ln u du. > > > > Any help is appreciated! Thanks! This is just a practice problem for a final and not something I have to turn in.
I haven't looked through all the comments closely yet but to clear things up I did mean the integral of ln(1+x)  (1+x^2)
Also, this is a practice problem for a Real Analysis II class. I wish I as still in Calc II. Thanks for the replies!



