Results 1 to 3 of 3

Math Help - Trigonometry involving Theta

  1. #1
    Junior Member
    Joined
    Sep 2008
    Posts
    30

    Trigonometry involving Theta #2

    So my teacher is bad at explaining so I need your help.

    1. If cosθ = \dfrac{1}{3} and 0 ≤ 2θ ≤ , find sin θ.

    2. Find all θ in the interval [0,2) that satisfy the equation: sinθ = \dfrac{1}{2}.
    Number 2 is suppose to be:
    Find all θ in the interval [0,2) that satisfy the equation:  \sin {\theta} - \sin {\theta} \cot {\theta} = 0



    Tips are kind of helpful, but step-by-step views will surely help in understanding it thoroughly...
    Thank You!
    Last edited by meiyukichan; November 30th 2008 at 09:39 PM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member
    Joined
    Mar 2008
    Posts
    128
    Quote Originally Posted by meiyukichan View Post
    So my teacher is bad at explaining so I need your help.

    1. If cosθ = \dfrac{1}{3} and 0 ≤ 2θ ≤ , find sin θ.

    2. Find all θ in the interval [0,2) that satisfy the equation: sinθ = \dfrac{1}{2}.


    Tips are kind of helpful, but step-by-step views will surely help in understanding it thoroughly... if that makes sense.
    Thank You!
    2.

    Keep in mind that saying \sin{\theta}=\frac{1}{2} is the exact same as \sin^{-1}(\frac{1}{2})=\theta which literally says "find the angle \theta whose sine equals \frac{1}{2}.

    Also, think about the unit circle...where is the sine function positive? You are only going to have two answers on the interval [0,2\pi)
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Sep 2008
    Posts
    30
    Quote Originally Posted by elizsimca View Post
    2.

    Keep in mind that saying \sin{\theta}=\frac{1}{2} is the exact same as \sin^{-1}(\frac{1}{2})=\theta which literally says "find the angle \theta whose sine equals \frac{1}{2}.

    Also, think about the unit circle...where is the sine function positive? You are only going to have two answers on the interval [0,2\pi)

    Sorry. Really, really sorry. I posted the wrong question.

    It's suppose to be:
    Find all θ in the interval [0,2) that satisfy the equation:  \sin {\theta} - \sin {\theta} \cot {\theta} = 0
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 2
    Last Post: March 29th 2010, 07:38 AM
  2. Expressions involving trigonometry
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: March 13th 2010, 02:06 PM
  3. Trigonometry involving Theta
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: December 1st 2008, 05:42 AM
  4. Derivatives involving trigonometry
    Posted in the Calculus Forum
    Replies: 2
    Last Post: January 16th 2007, 07:08 PM
  5. Algebraic Manipulation involving Trigonometry
    Posted in the Advanced Algebra Forum
    Replies: 2
    Last Post: October 26th 2005, 10:27 AM

Search Tags


/mathhelpforum @mathhelpforum