Results 1 to 4 of 4

Thread: Proving second derivative

  1. #1
    Senior Member
    Joined
    Mar 2017
    From
    Toronto
    Posts
    292
    Thanks
    2

    Question Proving second derivative

    Hi,

    I hope someone can help me with the following question:

    Proving second derivative-screen-shot-2017-09-05-9.25.40-pm.png

    I got a different expression for the second derivative than the one above. I'm wondering whether I'm solving this incorrectly or the textbook solution is just wrong. The textbook solution is as follows:

    Proving second derivative-screen-shot-2017-09-05-9.23.08-pm.png

    Let me know.

    - olivia
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2010
    Posts
    2,971
    Thanks
    1141

    Re: Proving second derivative

    Quote Originally Posted by otownsend View Post
    Hi,

    I hope someone can help me with the following question:

    Click image for larger version. 

Name:	Screen Shot 2017-09-05 at 9.25.40 PM.png 
Views:	6 
Size:	99.5 KB 
ID:	38075

    I got a different expression for the second derivative than the one above. I'm wondering whether I'm solving this incorrectly or the textbook solution is just wrong. The textbook solution is as follows:

    Click image for larger version. 

Name:	Screen Shot 2017-09-05 at 9.23.08 PM.png 
Views:	6 
Size:	196.0 KB 
ID:	38076

    Let me know.

    - olivia
    The textbook is correct
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor

    Joined
    Apr 2005
    Posts
    19,415
    Thanks
    2889

    Re: Proving second derivative

    You say you "got a different expression for the second derivative" but don't say what you got. If you would show what you did and what expression you got, we could point out your error. That will help you more than just pointing out that you are wrong.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Senior Member
    Joined
    Mar 2017
    From
    Toronto
    Posts
    292
    Thanks
    2

    Re: Proving second derivative

    Yeah sorry, I understand now where I went wrong. Don't need help anymore
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. proving u has a derivative at x=0
    Posted in the Calculus Forum
    Replies: 6
    Last Post: Apr 20th 2013, 04:34 PM
  2. Proving a derivative.
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Apr 20th 2011, 03:19 PM
  3. proving derivative
    Posted in the Calculus Forum
    Replies: 3
    Last Post: Mar 19th 2010, 03:10 PM
  4. Replies: 2
    Last Post: Nov 6th 2009, 03:51 PM
  5. Proving the derivative.
    Posted in the Calculus Forum
    Replies: 2
    Last Post: Oct 6th 2009, 07:40 PM

Search Tags


/mathhelpforum @mathhelpforum