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

I I can't understand the fact

  1. Jun 17, 2016 #1
    I can's understand the fact about the equation

    i cant prove the equation from the first attachment to the second attachment pls help.

    Sorry for bad english
     

    Attached Files:

  2. jcsd
  3. Jun 17, 2016 #2

    andrewkirk

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    The second last formula is ##\frac{dx}{dy}\frac d{dx}\left(\frac{dy}{dx}\right)^{-1}##.
    If we write ##y'## for ##\frac{dy}{dx}## then that is
    $$\frac1{y'}\frac d{dx}\left(\frac 1{y'}\right)$$
    What happens when you perform the differentiation?
     
  4. Jun 17, 2016 #3
    Thank you very much, I can understand now why it has a negative sign
     
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: I can't understand the fact
Loading...