Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I Tangent plane in Zee text

  1. Mar 6, 2016 #1
    In Zee "Einstei gravity in a nutshell" section I.6, page 83, the author says about the approxiamtion of the south pole of sphere

    pic1.PNG

    How is the first equation approximated by the second? One page later he does this expansion again.

    pic2.PNG
    Is this thecalculus Leibnitz rule? Or some clever trick?

    Thank you!
     
  2. jcsd
  3. Mar 6, 2016 #2

    Ibix

    User Avatar
    Science Advisor

    It's the series approximation for ##\sqrt {1-a}##, with ##a=(x^2+y^2)/L^2##. He just neglects terms above first order in ##a##.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Tangent plane in Zee text
  1. Online text (Replies: 2)

  2. Original Text(s) (Replies: 6)

Loading...