Results 1 to 4 of 4

Math Help - Linear Trigonomic Equation

  1. #1
    Newbie
    Joined
    Sep 2009
    Posts
    20

    Linear Trigonomic Equation

    Just a word problem thats bugging me:

    The height, in metres, of a nail in a water wheel above the surface of the water, as a function of time, can be modelled by: h(t)=-4sin pi/4 (t-1) + 2.5 where t is time in seconds. During what periods of time is the nail below the water in the first 24 s that the wheel is roatating...

    There is a similar proble, in the book which outlines how you would solve it, except that there are no brackets (where the t-1 is) so this is throwing me off, because I don't know how to get to the next step after that and everything i've tried has been wrong.

    Thanks a lot in advance!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    11,689
    Thanks
    448
    Quote Originally Posted by abc10 View Post
    Just a word problem thats bugging me:

    The height, in metres, of a nail in a water wheel above the surface of the water, as a function of time, can be modelled by: h(t)=-4sin pi/4 (t-1) + 2.5 where t is time in seconds. During what periods of time is the nail below the water in the first 24 s that the wheel is roatating...

    There is a similar proble, in the book which outlines how you would solve it, except that there are no brackets (where the t-1 is) so this is throwing me off, because I don't know how to get to the next step after that and everything i've tried has been wrong.

    Thanks a lot in advance!
    you were already provided with a most thorough solution ... what/where is your problem with it?

    S.O.S. Mathematics CyberBoard :: View topic - Linear Trig Equation Word Problem
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2009
    Posts
    20
    Wow! Haha, I didn't know that page existed, I didn't post that but obviously its sufficient. Thank you.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,236
    Thanks
    28
    Why not say


    0=-4\sin \frac{\pi}{4} (t-1) + 2.5

    -2.5=-4\sin \frac{\pi}{4} (t-1)

    0.0625 = \sin \frac{\pi}{4} (t-1)

    \sin^{-1}(0.0625) =  \frac{\pi}{4} (t-1)

    \frac{4}{\pi}\sin^{-1}(0.0625) =  t-1

    \frac{4}{\pi}\sin^{-1}(0.0625)+1 =  t


    Is this the only soln? ;0)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Help with trigonomic equation...
    Posted in the Trigonometry Forum
    Replies: 8
    Last Post: July 18th 2011, 07:23 PM
  2. Trigonomic graph
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: August 9th 2010, 11:16 AM
  3. trigonomic identities
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: January 21st 2010, 02:04 PM
  4. Trigonomic Identities Help?
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: December 18th 2008, 03:42 PM
  5. Trigonomic Identities
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: June 20th 2007, 02:01 PM

Search Tags


/mathhelpforum @mathhelpforum