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Logarithmic Differentiation

  1. Apr 6, 2005 #1
    Can someone please differentiate this [itex] \!\(Log\\_2\[[x^3 + 1][/itex]
    im stuck because its base 2
  2. jcsd
  3. Apr 6, 2005 #2
    Remember that [tex]\log_a{x}=\frac{\log_b{x}}{\log_b{a}}[/tex]
  4. Apr 6, 2005 #3
    so is this my next step? and then do i use quotient rule?
  5. Apr 6, 2005 #4
    You don't need the quotient rule because ln2 is a constant.
  6. Apr 6, 2005 #5
    so is the the answer then?
  7. Apr 6, 2005 #6


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    He used the chain rule just fine.

    He just forgot how to deal with a constant multiple. Hint: what's the derivative of 6 x^2?
  8. Apr 6, 2005 #7
    ah, thanks
  9. Apr 6, 2005 #8


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    And [itex] \ln 2[/itex] should be there somewhere.In the denominator,to be precise.

    And the thread title,to be accurate,should have been "logarithm('s) derivative"...

  10. Apr 6, 2005 #9


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    I deleted my response because he changed his post before I submitted, or it displayed incorrectly on my browser.
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