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Homework Help: How do you find a dervative of this

  1. Mar 22, 2008 #1
    how do you find the derivative of this problem and what rule do you use

    lim sin(pi+h)-Sin pi
    h-> 0 h
     
  2. jcsd
  3. Mar 22, 2008 #2

    tiny-tim

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    … sinπ = 0 …

    Hi janemba! :smile:

    Do you mean [tex]\frac{sin(\pi + h) -sin\pi}{h}[/tex] ?

    If so, remember that sinπ = 0, so it's just [tex]\frac{sin(\pi + h)}{h}\,.[/tex]

    Which is … ? :smile:
     
  4. Mar 23, 2008 #3
    yes but how did you got the answer
     
  5. Mar 23, 2008 #4
    How do you expand:

    [tex]sin(x+y)=???[/tex]

    Trig identity ...
     
  6. Mar 23, 2008 #5

    Gib Z

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    It's even simpler than that, take a look at a unit circle and think about what happens with every rotation of pi radians.
     
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