Results 1 to 7 of 7

Math Help - derivative with an e function

  1. #1
    Member
    Joined
    Oct 2009
    Posts
    79

    derivative with an e function

    Find the derivative of the function. y=e^(2xsinx) [e raised to 2xsin(x)]


    e^u=e^udu


    y=e^(2xsinx)du

    product rule
    e^(2xsin(x))[(2sinx+2xcosx)]
    Where did I falter?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Jun 2009
    From
    United States
    Posts
    676
    Thanks
    19
    Quote Originally Posted by hazecraze View Post
    Find the derivative of the function. y=e^(2xsinx) [e raised to 2xsin(x)]


    e^u=e^udu

    I don't understand what you did here. There shouldn't be a du. If you are defining u=2xin(x) then the function should be written y=e^u. I think you are treating this as if it were an integral.


    y=e^(2xsinx)du

    product rule
    e^(2xsin(x))[(2sinx+2xcosx)]
    Where did I falter?

    So now just find \frac{dy}{dx}=\frac{dy}{du}\frac{du}{dx} were y=e^u and u=2xsin(x).
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Banned
    Joined
    Oct 2009
    Posts
    4,261
    Thanks
    2
    Quote Originally Posted by hazecraze View Post
    Find the derivative of the function. y=e^(2xsinx) [e raised to 2xsin(x)]


    e^u=e^udu


    y=e^(2xsinx)du

    product rule
    e^(2xsin(x))[(2sinx+2xcosx)]
    Where did I falter?
    Nowhere: it is correct.

    Tonio
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Member
    Joined
    Oct 2009
    Posts
    79
    Quote Originally Posted by tonio View Post
    Nowhere: it is correct.

    Tonio
    hmm...the online grader says it's wrong. What else could I do, move the 2 from the 2sinx+blah to the front?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor
    Joined
    Oct 2008
    Posts
    1,035
    Thanks
    49
    Probably it needs sin(x) not sinx
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Member
    Joined
    Oct 2009
    Posts
    79
    Quote Originally Posted by tom@ballooncalculus View Post
    Probably it needs sin(x) not sinx
    This is how it looked when I submitted it:
    y'=
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Banned
    Joined
    Oct 2009
    Posts
    4,261
    Thanks
    2
    Quote Originally Posted by hazecraze View Post
    This is how it looked when I submitted it:
    y'=

    Ok, THIS is incorrect and very different from what you wrote in your prior post! Just add a left parentheses before 2\sin x and a right parentheses at the end and it again will be correct

    Tonio
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Function having a third derivative
    Posted in the Differential Geometry Forum
    Replies: 5
    Last Post: January 21st 2011, 12:52 PM
  2. derivative of a function
    Posted in the Differential Geometry Forum
    Replies: 9
    Last Post: December 3rd 2009, 02:10 PM
  3. Derivative of a log function
    Posted in the Calculus Forum
    Replies: 6
    Last Post: August 4th 2009, 10:04 PM
  4. derivative function
    Posted in the Calculus Forum
    Replies: 3
    Last Post: August 1st 2009, 10:48 PM
  5. Derivative of a function
    Posted in the Calculus Forum
    Replies: 6
    Last Post: March 18th 2009, 07:29 PM

Search Tags


/mathhelpforum @mathhelpforum