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Trouble with the unit normal vector for stokes theorem

  1. May 9, 2012 #1
    We're given x^2+2*y^2=1.
    so x^2=1-2y^2

    now using distance formula
    d^2=x^2+y^2
    since x^2=1-2y^2, substituting it in the distance formula we get:
    d^2=1-2y^2+y^2=1-y^2;
    differentiating and then setting the eq to 0 we get;
    0=-4y
    or y=0. now x^2=1-2y^2=1
    so x=+-1
    so point having min distance form origin is (+-1,0)

    using the distance formula now
    d^2=x^2+y^2
    d=sqrt(1+0)=1
     
  2. jcsd
  3. May 9, 2012 #2
    Sorry. Wrong post. I intended to preview it but posted it by mistake.
     
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