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Math Help - Solving Limit with Absolute Values

  1. #1
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    Solving Limit with Absolute Values

    the lim as h-->0 of (|x+h|-|x|)/h at x=3 is
    A) -1 B) 0 C) 1 D) 3 E) nonexistent
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  2. #2
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    Quote Originally Posted by rawkstar View Post
    the lim as h-->0 of (|x+h|-|x|)/h at x=3 is
    A) -1 B) 0 C) 1 D) 3 E) nonexistent
    note that this is the definition of a derivative for the function f(x) = |x|

    remember what the graph of y = |x| looks like?

    so ... what is f'(3) = ?
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    f(3)=f(-3)?
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  4. #4
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    nevermind

    I found that |x+h|-|x|=|h|
    so |h|/h=h/h=1
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