Results 1 to 2 of 2

Math Help - how do you choose which half angle formula (tan) to use?

  1. #1
    Member
    Joined
    Jan 2008
    Posts
    83

    how do you choose which half angle formula (tan) to use?

    Mathwords: Half Angle Identities

    for tangent u/2, it shows two formulas.

    how do you know which one to use? or do they equal the same thing

    1-cos u / sin u

    or

    sin u / 1 + cos u
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,842
    Thanks
    320
    Awards
    1
    Quote Originally Posted by algebra2 View Post
    Mathwords: Half Angle Identities

    for tangent u/2, it shows two formulas.

    how do you know which one to use? or do they equal the same thing

    1-cos u / sin u

    or

    sin u / 1 + cos u
    They are all the same. (Note that all of them carry the +/- symbol on them. The page wasn't too clear about that.) Which you pick is determined by which is the most useful to you.

    -Dan
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Write (Cos(5x))^2 using half angle formula
    Posted in the Trigonometry Forum
    Replies: 5
    Last Post: November 2nd 2010, 03:01 PM
  2. Double/half angle formula
    Posted in the Trigonometry Forum
    Replies: 3
    Last Post: April 8th 2010, 09:41 AM
  3. Half-Angle Formula Help
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: November 4th 2009, 04:18 PM
  4. half angle formula
    Posted in the Calculus Forum
    Replies: 2
    Last Post: April 27th 2009, 04:39 PM
  5. Using half angle formula
    Posted in the Trigonometry Forum
    Replies: 6
    Last Post: March 27th 2006, 03:50 AM

Search Tags


/mathhelpforum @mathhelpforum