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Homework Help: This equation is NOT exact, correct?

  1. Apr 15, 2010 #1
    1. The problem statement, all variables and given/known data
    (2y^2 - 4x + 5) dx = (4-2y+4xy)dy

    i divided by dx and rearranged...

    (-2y^2 + 4x - 5) + (4-2y+4xy)dy/dx
    this is M.............and this is N

    then took partial derivatives...

    M_y = -4y

    N_x = 4y

    M_y not equal to N_x, therefore not exact..

    but it is so close that i suspect i am making some mistake..

    ??



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Apr 15, 2010 #2

    Mark44

    Staff: Mentor

    Correct, it's not exact. Be careful, though - you started with an equation and lost the = in your next line.

    Here's a better rearrangement.

    (2y^2 - 4x + 5) dx + (-4 + 2y - 4xy)dy = 0
    (........M.........)........(.........N.......)
     
  4. Apr 15, 2010 #3
    thANKS.. shouldve been..
    (-2y^2 + 4x - 5) + (4-2y+4xy)dy/dX = 0
     
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