1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Line Integral - Vector Calculus

  1. Mar 31, 2012 #1
    1. The problem statement, all variables and given/known data
    Calculate the line integral:
    f(x,y) = (x² - 2xy)î + (y² - 2xy)j, between the points (-1,1) and (1,1) along the parabola y = x².
    (resp: -14/15)


    The attempt at a solution
    I thought something like this: substitue y = x², and then integrate de f(x,y). And then evaluate from -1 to 1, but it didn't work, obviously. How should I start solving this? I think I didn't get the concept about this kind of exercise...
     
  2. jcsd
  3. Mar 31, 2012 #2

    HallsofIvy

    User Avatar
    Science Advisor

    If it didn't work then you must have made an error in the integrall. What, exactly, did you do?

    The integral of this will be [itex]\int (x^2 - 2xy)dx+ (y^2- 2xy)dy[//itex]. Did you remember to put dy in terms of x also?
     
  4. Mar 31, 2012 #3
    Ahh, that's exactly what I was forgetting! Thank you!!
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook