Results 1 to 4 of 4

Math Help - [SOLVED] Basic Integration

  1. #1
    Member
    Joined
    Sep 2009
    Posts
    148

    Cool [SOLVED] Basic Integration

    Here's a question from a past paper



    I have attempted the first part and my values are:

    K = +8 or -8 C = 2

    Whereas the answer in the marking scheme states K = 32 and C = 2
    Is there a mistake in the marking scheme because the value of K can't be 32 if the value of C is 2 ... right?

    Thanks!

    P.S

    My equation of the curve comes out to be

    y=k^2/4x^2+c
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Feb 2008
    Posts
    383
    Quote Originally Posted by unstopabl3 View Post
    Here's a question from a past paper



    I have attempted the first part and my values are:

    K = +8 or -8 C = 2

    Whereas the answer in the marking scheme states K = 32 and C = 2
    Is there a mistake in the marking scheme because the value of K can't be 32 if the value of C is 2 ... right?

    Thanks!

    P.S

    My equation of the curve comes out to be

    y=k^2/4x^2+c
    -\frac{k}{x^3} = -kx^{-3}

    \int -kx^{-3} \rightarrow \frac{-k}{-2}x^{-2} +c

    then we know it goes through two points.

    sub it in the equation. y= \frac{-k}{-2}x^{-2} +c

    we have 18= \frac{-k}{-2}1^{-2} +c

    and 3= \frac{-k}{-2}4^{-2} +c .

    now we have 2 simultaneous equations.

    solve to find k and c. which comes to your mark scheme answer.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor undefined's Avatar
    Joined
    Mar 2010
    From
    Chicago
    Posts
    2,340
    Awards
    1
    By the way, I'm not sure why you thought this question belonged in the Pre-Algebra and Algebra subforum since it is clearly a calculus problem.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Member
    Joined
    Sep 2009
    Posts
    148
    Thanks, sorry for the mix up, as the question was so basic I thought it belonged in the basic forums. Nevertheless, thanks for moving it, although I don't think this belongs in the university level calculus, maybe in the high-school calculus forum.

    Thanks anyways!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: November 3rd 2010, 12:54 AM
  2. [SOLVED] Basic Integration
    Posted in the Calculus Forum
    Replies: 4
    Last Post: May 17th 2010, 04:37 AM
  3. basic integration
    Posted in the Calculus Forum
    Replies: 4
    Last Post: March 3rd 2010, 10:30 AM
  4. Basic Integration
    Posted in the Calculus Forum
    Replies: 1
    Last Post: September 8th 2009, 08:33 AM
  5. Basic Integration
    Posted in the Calculus Forum
    Replies: 3
    Last Post: February 1st 2009, 12:58 PM

Search Tags


/mathhelpforum @mathhelpforum