Results 1 to 2 of 2

Math Help - Find derivatives of functions

  1. #1
    Newbie
    Joined
    Nov 2006
    Posts
    13

    Find derivatives of functions

    Alright, I have two questions. The first I think I have right, but I just want to make sure. The 2nd I have little or no clue on. Anyways, thanks in advance for the help.

    Use the rules for derivatives to find the derivative of each function defined as follows

    1.) y = 8e^5x

    I came up with dy/dx = 40^5x by simply multiplying 8 by 5 eliminating the e and keeping the exponent. This appeared to be the process based on an example problem I looked at. Am I right...close...or way off?

    2nd problem is from another section and I am lost

    Find the derivative of each function defined as follows

    2.) y = (2x^3 + 9x)^5
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    10
    Quote Originally Posted by Mathamateur View Post
    Alright, I have two questions. The first I think I have right, but I just want to make sure. The 2nd I have little or no clue on. Anyways, thanks in advance for the help.

    Use the rules for derivatives to find the derivative of each function defined as follows

    1.) y = 8e^5x

    I came up with dy/dx = 40^5x by simply multiplying 8 by 5 eliminating the e and keeping the exponent. This appeared to be the process based on an example problem I looked at. Am I right...close...or way off?
    I think you mean,
    y=8*e^(5x)
    In that case,
    y'=40*e^(5x)
    You are correct!


    2nd problem is from another section and I am lost

    Find the derivative of each function defined as follows

    2.) y = (2x^3 + 9x)^5
    y=u^5
    u=2x^3+9x

    dy/du=5u^4
    du/dx=6x^2+9
    Thus,
    dy/du*du/dx=dy/dx=(6x^2+9)(5u^4)
    Substitute,
    5(6x^2+9)(2x^3+9x)^4
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. derivatives of functions
    Posted in the Differential Geometry Forum
    Replies: 3
    Last Post: October 16th 2011, 04:16 PM
  2. Replies: 4
    Last Post: February 10th 2009, 10:54 PM
  3. Help! functions and derivatives
    Posted in the Calculus Forum
    Replies: 2
    Last Post: December 18th 2008, 07:19 PM
  4. derivatives of ln functions
    Posted in the Calculus Forum
    Replies: 1
    Last Post: October 7th 2008, 10:14 PM
  5. Replies: 1
    Last Post: April 15th 2008, 10:00 AM

Search Tags


/mathhelpforum @mathhelpforum