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

Trignometry Proof Help

  1. Apr 8, 2010 #1
    Trignometry Proof Help!!!

    If a,b,c are sides in a triangle such that a<1/2(b+c) show that angle A (the angle opposite to side a) is less than 60 degrees
     
    Last edited: Apr 8, 2010
  2. jcsd
  3. Apr 8, 2010 #2

    mathman

    User Avatar
    Science Advisor
    Gold Member

    Re: Trignometry Proof Help!!!

    Have you tried the law of cosines?

    a2=b2+c2-2bccosA
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Trignometry Proof Help
  1. Help with a Proof (Replies: 5)

  2. Proof help (Replies: 2)

  3. Help with the proof (Replies: 10)

  4. Proof help? (Replies: 4)

Loading...