Results 1 to 2 of 2

Math Help - question regarding derivatives of inverse functions

  1. #1
    Newbie
    Joined
    Mar 2007
    Posts
    2

    question regarding derivatives of inverse functions

    please show all steps for the following problem

    Find (f^-1)^' (7) for the function f(x) = x^3 - (x/2), x > 0

    any help would be appreciated
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Junior Member frenzy's Avatar
    Joined
    Mar 2007
    From
    Planet Express
    Posts
    58
    Quote Originally Posted by sandra17 View Post
    please show all steps for the following problem

    Find (f^-1)^' (7) for the function f(x) = x^3 - (x/2), x > 0

    any help would be appreciated
    first we need to find f^(-1)(7)

    so we want a solution to

    f(x)=7

    x^3 - (x/2)=7

    x=2 works

    so

    f^(-1)(7)=2

    -----
    now find f'(x)

    f'(x)=3x^2-1/2
    ----

    finally

    (f^-1)^' (7)=1/[f'(f^(-1)(7))]
    =1/[f'(2)]=1/(3(2)^2-1/2)=1/(23/2)=2/23
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Inverse functions and their derivatives.
    Posted in the Calculus Forum
    Replies: 3
    Last Post: November 23rd 2011, 03:13 PM
  2. derivatives of inverse functions
    Posted in the Calculus Forum
    Replies: 2
    Last Post: November 22nd 2009, 04:51 AM
  3. Derivatives of Inverse Functions
    Posted in the Calculus Forum
    Replies: 3
    Last Post: November 12th 2009, 05:18 AM
  4. Replies: 4
    Last Post: February 10th 2009, 10:54 PM
  5. Derivatives of Inverse Functions
    Posted in the Calculus Forum
    Replies: 1
    Last Post: October 20th 2008, 08:48 PM

Search Tags


/mathhelpforum @mathhelpforum