1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

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
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook