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!

Simple Chain Rule Question

  1. Mar 4, 2013 #1
    1. The problem statement, all variables and given/known data

    Use chain rule to find the derivative of f(x)= sin(x)/(1+x^2)

    2. Relevant equations

    Chain Rule (f(g(x)))'*g'(x)

    3. The attempt at a solution
    y'(x)= cos (x)/(1+x^2)* (1-x^2)/((1+x^2)^2)

    I just want to make sure I am doing it correctly and this would be acceptable as a final answer.
     
  2. jcsd
  3. Mar 4, 2013 #2

    SammyS

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    Hello parents. Welcome to PF !

    Is the function [itex]\ \displaystyle f(x)=\frac{\sin(x)}{1+x^2} \,,[/itex]

    or is it [itex]\ \displaystyle f(x)=\sin\left(\frac{x}{1+x^2}\right) \ ?[/itex]
     
  4. Mar 4, 2013 #3
    Sorry! I see how that can be confusing. It's [itex]\ \displaystyle f(x)=\sin\left(\frac{x}{1+x^2}\right) [/itex]

    I am working on trying to put in equations correctly
     
  5. Mar 4, 2013 #4
    Make the equation f(u)=sin(u). Then take the derivative of sin(u) then multiply by the derivative of u.

    So:
    f'(u)=sin(u)'u'
     
    Last edited: Mar 4, 2013
  6. Mar 4, 2013 #5
    Your answer looks good to me.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Simple Chain Rule Question
  1. Chain Rule Question (Replies: 2)

  2. Chain Rule Question (Replies: 2)

  3. A chain rule question (Replies: 2)

Loading...