Results 1 to 2 of 2

Math Help - Finding the exact value

  1. #1
    Newbie
    Joined
    May 2008
    Posts
    10

    Finding the exact value

    of this expression is driving me crazy...

    sin(2sin^(-1)(-2/5))




    anyone willing to enlighten me?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by gabrie30 View Post
    of this expression is driving me crazy...

    sin(2sin^(-1)(-2/5))




    anyone willing to enlighten me?
    Let \alpha = \sin^{-1} \left( - \frac{2}{5} \right) \Rightarrow \sin \alpha = - \frac{2}{5}.

    You want the value of \sin (2 \alpha) = 2 \sin \alpha \cos \alpha.

    I will assume you can find \cos \alpha given \sin \alpha = - \frac{2}{5} ......
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Finding the exact value of sin 3
    Posted in the Trigonometry Forum
    Replies: 12
    Last Post: April 14th 2012, 03:25 AM
  2. finding the exact value..
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: April 26th 2010, 08:44 AM
  3. finding the exact value
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: December 30th 2009, 04:25 PM
  4. Finding the exact value using CAS
    Posted in the Calculators Forum
    Replies: 2
    Last Post: March 30th 2009, 03:58 AM
  5. Finding Exact Value
    Posted in the Trigonometry Forum
    Replies: 8
    Last Post: December 8th 2007, 09:15 AM

Search Tags


/mathhelpforum @mathhelpforum