Results 1 to 6 of 6

Math Help - cosine problem

  1. #1
    Junior Member
    Joined
    Mar 2012
    From
    San Francisco
    Posts
    32

    Question cosine problem

    Find the smallest number 'x' such that cos(ex + 1.2) = 0

    Give exact answer in terms of elementary functions.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,605
    Thanks
    1574
    Awards
    1

    Re: cosine problem

    Quote Originally Posted by jonathanraxa View Post
    Find the smallest number 'x' such that cos(ex + 1.2) = 0
    Give exact answer in terms of elementary functions.
    Let's see, is that a request for help or a demand for a solution?
    I am not sure why you have the right to demand help. Do you?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    11,407
    Thanks
    1294

    Re: cosine problem

    Quote Originally Posted by jonathanraxa View Post
    Find the smallest number 'x' such that cos(ex + 1.2) = 0

    Give exact answer in terms of elementary functions.
    Have you tried thinking about the values of \displaystyle \begin{align*} \theta \end{align*} which make \displaystyle \begin{align*} \cos{\theta} = 0 \end{align*}?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Junior Member
    Joined
    Mar 2012
    From
    San Francisco
    Posts
    32

    Re: cosine problem

    No, this is directly off my homework. I definitely do not have the right to demand help. I'm just terrible at math and for the questions I do not know I put them on here for people to perhaps help me, but apparently I'm getting help with the way I ask my questions.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Senior Member
    Joined
    Mar 2012
    From
    Sheffield England
    Posts
    440
    Thanks
    76

    Re: cosine problem

    To be fair I think that line was part of the question.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Senior Member
    Joined
    Mar 2012
    From
    Sheffield England
    Posts
    440
    Thanks
    76

    Re: cosine problem

    cos(e^x+1.2)=0
    e^x+1.2=pi/2 (must work in radians)
    e^x=pi/2-1.2
    x=ln(pi/2-1.2
    Give an exact answer means leave it like this.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: June 22nd 2011, 12:43 PM
  2. An awkward cosine problem
    Posted in the Calculus Forum
    Replies: 4
    Last Post: October 19th 2010, 10:16 AM
  3. Law of sine and cosine problem
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: May 8th 2010, 04:10 PM
  4. cosine problem
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: September 12th 2007, 01:29 PM
  5. cosine law - word problem
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: January 14th 2007, 08:50 AM

Search Tags


/mathhelpforum @mathhelpforum