1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Differntiate the function

  1. Jun 2, 2010 #1
    ok just want a check of my work before i send it :)

    differntiate the function;
    f(x)=[tex]\frac{x(20-x)}{36}[/tex]

    so,
    f'(x)=[tex]\frac{(20x-x^2)}{36}[/tex]

    f'(x)=[tex]\frac{(20-2x)}{36}[/tex]

    f'(x)=[tex]\frac{(10-2x)}{18}[/tex]

    Then....use the composite rule and your answer above to differntiate the function
    g(x)=ex(20-x)/36

    g'(x)=f'(x)*ef(x)

    so,
    g'(x)=[tex]\frac{10-2x)}{18}[/tex]*g(x)=ex(20-x)/36

    is this correct?

    is this correct
     
  2. jcsd
  3. Jun 2, 2010 #2

    Mark44

    Staff: Mentor

    Re: differentiation

    Above - This is not f'(x). All you have done is expand the numerator on the right. This should be f(x) = ...
    Above - Now you have taken the derivative
    Above - now you have an error. 20 - 2x != 2(10 - 2x).
    Where f(x) = (1/36)(x(20 - x)). The derivative below is incorrect. To fix it, replace f'(x) and f(x) where they appear.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Differntiate the function
  1. Differntial Equations (Replies: 1)

  2. Differntiation Problem (Replies: 1)

Loading...