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Homework Help: Single equation with 2 unknowns

  1. Mar 23, 2006 #1
    hiya, if i have the equation:
    y=0.2sin(5x-1100t)
    and i need what t = when y - 0.1

    how do i do this without knowing x / how do i find x????
    thanks u
    - kait
     
  2. jcsd
  3. Mar 23, 2006 #2

    lightgrav

    User Avatar
    Homework Helper

    You can't solve a single equation with 2 unknowns.
    The x-value to use is hidden in the wording of the problem scenario ...
    ... probably the origin , x= 0 .

    OR,
    they want the time for a piece of string to go from y = .2 (say)
    to y = -.01 , which means you get to choose your x - location.
     
  4. Mar 24, 2006 #3
    would finding the wavelength not help at all? is x the wavelength??
    or no...
     
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