Simple line integral problem I cant seem to get

  • Thread starter gr3g1
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  • #1
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I have to evaluate the line integral :
[itex]\oint_{}^{} (2x + y)dx + xydy[/itex] between (-1,2) and (2,5)

on the curve: [itex]y = x + 3[/itex]

So, what I did was:
[itex]\int_{-1}^{2} (3x+3)dx + \int_{2}^{5} (x^{2} + 3x)dx [/itex]

However, this is wrong and im not sure why!
Can someone please guide me?
Thanks alot!

Homework Statement





Homework Equations





The Attempt at a Solution

 

Answers and Replies

  • #2
Dick
Science Advisor
Homework Helper
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You are parametrizing the curve by the value of x which goes from -1 to 2. In BOTH parts. Since you've expressed the dy part of the integral in terms of x, why are you using the y limits there?
 
  • #3
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Ahhh, thanks so much!
 

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