Results 1 to 4 of 4

Math Help - Using product rule to differentiate equations.

  1. #1
    Newbie
    Joined
    Sep 2011
    Posts
    15

    Using product rule to differentiate equations.

    h(x) = sq.root(t) * (1-t^2)

    and

    f(x)=x^3 cos x


    I know the answers, but I don't know how to differentiate with a square root involved or trig function involved. I need the work to show me what I'm suppose to do. Thanks!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member TheChaz's Avatar
    Joined
    Nov 2010
    From
    Northwest Arkansas
    Posts
    600
    Thanks
    2

    Re: Using product rule to differentiate equations.

    The derivative of cos(x) is -sin(x).

    So f '(x) = (x^3)' * cos(x) + x^3*(cos(x))' ...

    = (3x^2)cos(x) - sin(x)x^3
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2011
    Posts
    15

    Re: Using product rule to differentiate equations.

    Quote Originally Posted by TheChaz View Post
    The derivative of cos(x) is -sin(x).

    So f '(x) = (x^3)' * cos(x) + x^3*(cos(x))' ...

    = (3x^2)cos(x) - sin(x)x^3
    thanks!
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Sep 2011
    Posts
    15

    Re: Using product rule to differentiate equations.

    What about the square root problem?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] quick question on product rule and equality rule for logs
    Posted in the Pre-Calculus Forum
    Replies: 8
    Last Post: October 19th 2011, 08:29 PM
  2. Replies: 5
    Last Post: October 19th 2009, 02:04 PM
  3. Differentiate using product Rule
    Posted in the Calculus Forum
    Replies: 3
    Last Post: June 5th 2009, 09:40 AM
  4. Replies: 3
    Last Post: May 25th 2009, 09:39 AM
  5. use product rule to differentiate function
    Posted in the Calculus Forum
    Replies: 4
    Last Post: March 2nd 2008, 07:39 AM

Search Tags


/mathhelpforum @mathhelpforum