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Homework Help: Sinusoidal Functions Help

  1. Mar 24, 2015 #1
    image.jpg 1. The problem statement, all variables and given/known data
    A graph of y=f(x) is shown. Find the following function values and justify your answers.


    2. Relevant equations

    3. The attempt at a solution
    I know the graph is periodic, I know it's max and min, and I know it's amplitude because of that. But I don't know what the 30 or -14 is supposed to mean to me or how I'm suppose to "justify" my answer
  2. jcsd
  3. Mar 24, 2015 #2


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    It looks to me like what you are supposed to conclude from the graph is that f(x+4)=f(x). That's periodic. So f(-14)=f(-10)=f(-6)=f(-2). The last value you can read off from the graph. Patterns like that.
  4. Mar 24, 2015 #3
    f(30) and f(-14) are the values of the function calculated in x=30 and x=-14.
    You said that the graph is periodic, so it means that the graph repeat itself with perod 5.
    now you should obtain the two values.
  5. Mar 24, 2015 #4
    Yes, Dick is right, the period is 4
  6. Mar 24, 2015 #5


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    (It is possible for you to Edit post #3. )
  7. Mar 24, 2015 #6
    Now no more; I'll do it in future if I should realize in time to have to correct my post
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