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Math Help - differentiating

  1. #1
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    differentiating

    Hello, I am trying to understand how this was differentiated:
    1/3x^3

    I would have thought:
    -3x^-3
    9x^-4
    9/x^4

    but I know this wrong.
    Can someone please point out where I am going wrong ?

    Thanks kindly.
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  2. #2
    Super Member TheChaz's Avatar
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    Quote Originally Posted by fran1942 View Post
    Hello, I am trying to understand how this was differentiated:
    1/3x^3

    I would have thought:
    -3x^-3
    9x^-4
    9/x^4

    but I know this wrong.
    Can someone please point out where I am going wrong ?

    Thanks kindly.
    Is it 1/(3x^3) ??

    Then it's (1/3)x^-3, the derivative is
    -3(1/3)x^-4 = -1x^-4 = -1/x^4
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  3. #3
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    Quote Originally Posted by fran1942 View Post
    Hello, I am trying to understand how this was differentiated:
    1/3x^3

    I would have thought:
    -3x^-3
    This is your mistake. [itex]1/3= 3^{-1}[/itex], not [itex]-3[/itex]
    9x^-4
    9/x^4

    but I know this wrong.
    Can someone please point out where I am going wrong ?

    Thanks kindly.[/QUOTE]
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