Results 1 to 2 of 2

Math Help - Trig and Radians

  1. #1
    Junior Member
    Joined
    Aug 2008
    Posts
    57

    Trig and Radians

    I am really stuck with this question

    Given that cosec\theta = -\sqrt 2

    and tan \theta = -1

    and -\pi<0<\pi

    find the exact value of \theta in radians. Justify your answer.

    I keep trying to find the relationship by rearranging cosec in terms of cot and then tan but i'm not making any headway.

    I feel like I'm missing something really obvious. Can anyone point me in the right direction??

    Thanks
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Mar 2007
    Posts
    1,240

    Talking

    Quote Originally Posted by Ian1779 View Post
    Given that \csc\theta = -\sqrt{2}

    and \tan(\theta) = -1 and -\pi\, <\, 0\, <\,\pi

    find the exact value of \theta in radians. Justify your answer.
    The cosecant is the reciprocal of the sine, so the above is saying that the sine is negative, so you're in Quadrant III or Quadrant IV. Also, the tangent is negative, so you're in... what Quadrant?

    You have memorized the basic reference angle values, so you know the reference angle for \tan(\theta)\, =\, 1, and thus for \tan(\theta)\, =\, -1.

    So what must \theta be...?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Help with trig and radians
    Posted in the Trigonometry Forum
    Replies: 10
    Last Post: July 14th 2010, 05:24 AM
  2. Trig with radians
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 2nd 2010, 04:05 PM
  3. Two trig question with squares and radians
    Posted in the Trigonometry Forum
    Replies: 7
    Last Post: January 24th 2010, 11:43 AM
  4. trig-radians
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: September 16th 2007, 06:31 PM
  5. solving trig equations (in radians)
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 11th 2007, 06:25 PM

Search Tags


/mathhelpforum @mathhelpforum