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: Simple but cant solve it

  1. May 20, 2010 #1
    Can someone show me in steps how to manipulate this formula in attachement to obtain 1/(sqr(w^2+4)? Thanks

    Attached Files:

  2. jcsd
  3. May 20, 2010 #2

    jack action

    User Avatar
    Science Advisor
    Gold Member

    The two equations are not equal. Just replace w by any value and you'll see that both equations give different answers.
  4. May 20, 2010 #3


    User Avatar
    Homework Helper

    The best you can really get is:

    Last edited: May 20, 2010
  5. May 20, 2010 #4


    User Avatar
    Homework Helper

    You must have made a typo. The expression should be,

  6. May 20, 2010 #5
    Hmm, thats quite possible. Then how to get that solution?
  7. May 20, 2010 #6


    User Avatar
    Homework Helper

    Well I can't just give you the answer, you need to show an attempt at solving the problem first.

    But I can give you some hints, you can most certainly find the answer by using a combination of these rules:


    [tex]\sqrt{a^2b}=|a|\sqrt{b}[/tex] (the |a| means the positive of a, but remember that for any real number n, n2 is always positive).



    Good luck! :smile:
  8. May 21, 2010 #7
    Hello, I am sorry but it just does not work. What am I doing work? Thanks

    Attached Files:

    • 1.jpg
      File size:
      11.2 KB
  9. May 21, 2010 #8


    User Avatar
    Homework Helper

    You're adding fractions, but you're multiplying numerators.
  10. May 21, 2010 #9
    AAA, stupid me:) Thanks
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook