Results 1 to 4 of 4

Math Help - help with solving a half angle identity

  1. #1
    Junior Member
    Joined
    Jul 2009
    Posts
    36

    help with solving a half angle identity

    Im not exactly sure how the square root of 1-(-1/3)/2 = the square root of 2/3?

    Can someone explain this for me?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    11,829
    Thanks
    1602
    \displaystyle \sqrt{\frac{1 - \left(-\frac{1}{3}\right)}{2}} = \sqrt{\frac{1 + \frac{1}{3}}{2}}

    \displaystyle = \sqrt{\frac{\frac{4}{3}}{2}}

    \displaystyle = \sqrt{\frac{4}{6}}

    \displaystyle = \sqrt{\frac{2}{3}}.


    P.S. Please use brackets where they're needed, what you posted looks lke \displaystyle 1 - \frac{\left(-\frac{1}{3}\right)}{2}...
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Jul 2009
    Posts
    36
    so you go from \sqrt{\frac{\frac{4}{3}}{2}} to \displaystyle = \sqrt{\frac{2}{3}} by multiplying the 2 by the 3 and leaving the 4 ontop?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Junior Member
    Joined
    Jul 2009
    Posts
    36
    i think i understand, you dont know how much i appreshiate the help !
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. simplifying using half angle identity
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: March 10th 2010, 05:52 PM
  2. Replies: 0
    Last Post: March 1st 2010, 10:53 AM
  3. Solving Identity (I always get half the solutions)
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 7th 2009, 06:41 PM
  4. Half-Angle Identity
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: March 30th 2008, 06:35 AM
  5. [SOLVED] half-angle identity problem
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: January 1st 2006, 11:31 AM

Search Tags


/mathhelpforum @mathhelpforum