Results 1 to 3 of 3

Math Help - help Prove identities

  1. #1
    Newbie
    Joined
    Mar 2009
    Posts
    9

    help Prove identities

    Please guys can you help me prove the following identities

    si((n)^(2))θsecθ=sinθtanθ


    tan^2 A= ((sin^2A)/(1-si((n)^(2))A))



    2-((tan)^(2))A=2((sec)^(2))A-3((tan)^(2))A

    Any help would be greatly appreciated. Cheers!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member Showcase_22's Avatar
    Joined
    Sep 2006
    From
    The raggedy edge.
    Posts
    782
    Does si(n^2) \theta mean sin^2 (\theta)?

    For the second one, if you use tan \theta= \frac{sin \theta}{cos \theta} and double angle formulae you should get the answer.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Jan 2009
    Posts
    145
    #1) sin(x)^2*sec(x) = sin(x) * tan(x)
    sin(x) * sec(x) = tan(x)
    sin(x) * 1/cos(x) = sin(x)/cos(x)
    sin(x)/cos(x) = sin(x)/cos(x)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Prove some identities!
    Posted in the Math Challenge Problems Forum
    Replies: 105
    Last Post: December 29th 2010, 11:58 PM
  2. prove the following identities.
    Posted in the Trigonometry Forum
    Replies: 3
    Last Post: June 23rd 2010, 12:15 AM
  3. Prove these identities.
    Posted in the Trigonometry Forum
    Replies: 5
    Last Post: July 20th 2009, 10:42 PM
  4. Prove identities, can anyone help?
    Posted in the Trigonometry Forum
    Replies: 3
    Last Post: February 14th 2009, 02:04 PM
  5. Prove the following identities.............
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: July 16th 2008, 09:07 AM

Search Tags


/mathhelpforum @mathhelpforum