Results 1 to 2 of 2

Math Help - Integral. #4

  1. #1
    Member
    Joined
    Jan 2009
    Posts
    236

    Integral. #4

    hellloo
    I posted these problems for fun
    you can post full solutions
    its not for my homework
    I did not post them in the challenge problem sub-forum because i do not know the solutions .. also because am not ready to PM 20 persons

    heeeereeee is ittttt:
    Evaluate:

    \int \frac{dx}{\sqrt{-2x^2+3x+4}}
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member General's Avatar
    Joined
    Jan 2010
    From
    Kuwait
    Posts
    562
    Quote Originally Posted by TWiX View Post
    hellloo
    I posted these problems for fun
    you can post full solutions
    its not for my homework
    I did not post them in the challenge problem sub-forum because i do not know the solutions .. also because am not ready to PM 20 persons

    heeeereeee is ittttt:
    Evaluate:

    \int \frac{dx}{\sqrt{-2x^2+3x+4}}
    -2x^2+3x+4=-2(x^2 - \frac{3}{2}x-2)=-2 \left( \left(x - \frac{3}{4}\right)^2-\left( \frac{\sqrt{41}}{4} \right)^2 \right)
    =2\left( \left( \frac{\sqrt{41}}{4} \right)^2 - \left(x - \frac{3}{4}\right)^2 \right)

    So the integral will be : \frac{1}{\sqrt{2}} \int \frac{dx}{\sqrt{ \left( \frac{\sqrt{41}}{4} \right)^2 - \left(x - \frac{3}{4}\right)^2 }}<br />
    =\frac{1}{\sqrt{2}} sin^{-1}\left( \frac{4x-3}{\sqrt{41}} \right) + C
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 2
    Last Post: August 31st 2010, 07:38 AM
  2. Replies: 1
    Last Post: June 2nd 2010, 02:25 AM
  3. Replies: 0
    Last Post: May 9th 2010, 01:52 PM
  4. [SOLVED] Line integral, Cauchy's integral formula
    Posted in the Differential Geometry Forum
    Replies: 3
    Last Post: September 15th 2009, 01:28 PM
  5. Replies: 0
    Last Post: September 10th 2008, 07:53 PM

Search Tags


/mathhelpforum @mathhelpforum