Results 1 to 3 of 3

Math Help - Trig proof for sec^2

  1. #1
    Newbie
    Joined
    Jul 2010
    Posts
    1

    Trig proof for sec^2

    I have a proof in my trig book, that I am completely stumped on! I'm sure I am missing something easy, but just can't seem to get there.

    sec^2(x)=(sec(2x))(2-sec^2(x))

    Any hints?
    Thanks!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,236
    Thanks
    29
    Quote Originally Posted by tshenura View Post



    Any hints?
    What do you know \sec^2 x being equal to?

    Table of Trigonometric Identities
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Aug 2009
    From
    Mumbai
    Posts
    83
    Use the relation, \sec(2x) = (1+(\tan(x))^{2})/(1-(\tan(x))^{2}), and simplify.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Trig Proof
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: May 1st 2011, 06:23 AM
  2. Trig Proof
    Posted in the Trigonometry Forum
    Replies: 3
    Last Post: October 27th 2010, 06:55 PM
  3. Trig Proof
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: October 26th 2010, 04:55 PM
  4. trig proof
    Posted in the Trigonometry Forum
    Replies: 6
    Last Post: March 5th 2009, 11:57 PM
  5. Help with a Trig Proof
    Posted in the Calculus Forum
    Replies: 1
    Last Post: October 11th 2008, 12:16 PM

Search Tags


/mathhelpforum @mathhelpforum