Results 1 to 3 of 3
Like Tree1Thanks
  • 1 Post By Prove It

Thread: NEW USER NEED SUM HELP with this calculus prob. Derivative Prob.

  1. #1
    Newbie
    Joined
    Apr 2013
    From
    manila,phil.
    Posts
    7

    NEW USER NEED SUM HELP with this calculus prob. Derivative Prob.

    hi im jhay from.. phl. civil engr. student .. first time to take calculus..
    can u explain to me step by step of finding the derivative of a function x√(x-1) using four step rule .. big tnx in advance..
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    12,711
    Thanks
    1881

    Re: NEW USER NEED SUM HELP with this calculus prob. Derivative Prob.

    I don't know what you mean by the "four step rule". It is a product of two functions, so use the product rule. The second function also needs the use of the chain rule.
    Thanks from topsquark
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Joined
    Mar 2010
    Posts
    1,021
    Thanks
    263

    Re: NEW USER NEED SUM HELP with this calculus prob. Derivative Prob.

    I think these are the four steps that iamjhay is talking about:

    1. Write f(x+h) and f(x)

    2. Compute f(x+h) - f(x)

    3. Simplify \frac{f(x+h)-f(x)}{h}

    4. Find \lim_{h\to0}\frac{f(x+h)-f(x)}{h}

    We would call it computing the derivative from the definition.

    To iamjhay: I think this identity will get you over the difficult part:

    \sqrt{a}-\sqrt{b}=\frac{a-b}{\sqrt{a}+\sqrt{b}}

    If you're still having trouble, show us the work you've done so far and we'll help you with the next step.

    - Hollywood
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. NEW USER NEED SUM HELP with this calculus prob.
    Posted in the New Users Forum
    Replies: 1
    Last Post: Jun 24th 2013, 05:51 AM
  2. Another calculus prob
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Oct 17th 2010, 01:01 PM
  3. calculus 2: work prob.
    Posted in the Calculus Forum
    Replies: 0
    Last Post: Feb 1st 2009, 08:45 PM
  4. derivative word prob
    Posted in the Calculus Forum
    Replies: 3
    Last Post: Mar 19th 2008, 06:35 PM
  5. Calculus Optimization Word Prob
    Posted in the Calculus Forum
    Replies: 6
    Last Post: Dec 6th 2006, 07:14 AM

Search Tags


/mathhelpforum @mathhelpforum