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X*ln(x) = 1/2x^2*ln(x) - 1/4*x^2 not sure how they got it

  • Thread starter mr_coffee
  • Start date
  • #1
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Hello everyone!

I'm doing a line integral but i'm confused on the integration method used:

I got to integral 1 to 3 2*(x^4+xln(x) ); But they then have:
x^5/5 + 1/2x^2 * ln(x) - 1/4x^2 and i'm not sure how they got the last part, 1/2x^2 * ln(x) - 1/4x^2

Thanks!

u = x isn't what they did I don't think, and its been awhile so i'm rusty on integration XD
 

Answers and Replies

  • #2
Dick
Science Advisor
Homework Helper
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The 'hard' part is the integral of x*ln(x). And they just integrated by parts.
 
  • #3
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ahh thank you
 

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