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: :Implicit Differentiation Problem - Check my work?:

  1. Oct 2, 2005 #1
    :Implicit Differentiation Problem -- Check my work?:

    Think I placed this in the wrong forum...

    I've worked it -- can someone just check my work?

    Problem:

    xcosy+ycos=1

    My work:

    [x (d/x)cosy + cosy (d/dx)x] + [y (d/dx)cosx + cosx (d/dx)y] = (d/dx) 1

    -xsiny (dy/dx) + cos y - ysinx + cos x (dy/dx) = 0

    -xsiny (dy/dx) + cos y = ysinx - cosy

    dy/dx = (ysinx - cosy)/(-xsiny + cos x)


    Meanwhile, could someone help me with this one...

    squareroot (xy) = 1+(x^2)y
     
  2. jcsd
  3. Oct 2, 2005 #2
    this final answer is right.

    The second one is probably easier, have a go at it at least and we'll check the answer again?
     
  4. Oct 2, 2005 #3
    Well, the problem with that one is the idea that I can't even get the first step... the derivative of sqrt (xy)
     
  5. Oct 2, 2005 #4
    Square the equation.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook