Results 1 to 6 of 6

Math Help - Integration by Substitution!!

  1. #1
    Member
    Joined
    Nov 2007
    Posts
    112

    Integration by Substitution!!

    (d)

    i need some help with this one please..
    Follow Math Help Forum on Facebook and Google+

  2. #2
    o_O
    o_O is offline
    Primero Espada
    o_O's Avatar
    Joined
    Mar 2008
    From
    Canada
    Posts
    1,407
    u = 4+ x^{2}
    du = 2xdx \quad \Rightarrow \quad {\color{blue}\frac{du}{2} = x dx}

    Substitute in:
    \int \frac{{\color{blue}\frac{du}{2}}}{u^{2}} = \frac{1}{2} \int \frac{du}{u^{2}}
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Nov 2007
    Posts
    112
    Quote Originally Posted by o_O View Post
    u = 4+ x^{2}
    du = 2xdx \quad \Rightarrow \quad {\color{blue}\frac{du}{2} = x dx}

    Substitute in:
    \int \frac{{\color{blue}\frac{du}{2}}}{u^{2}} = \frac{1}{2} \int \frac{du}{u^{2}}

    i dont quite understand, can you please show how to do the entire thing thanks

    mathlete
    Follow Math Help Forum on Facebook and Google+

  4. #4
    o_O
    o_O is offline
    Primero Espada
    o_O's Avatar
    Joined
    Mar 2008
    From
    Canada
    Posts
    1,407
    What don't you understand? The last integral should be a standard one: \int x^{n} dx = \frac{x^{n+1}}{n+1} + C \quad x\neq -1

    Here you have n = -2 ...
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Member
    Joined
    Nov 2007
    Posts
    112
    Quote Originally Posted by o_O View Post
    What don't you understand? The last integral should be a standard one: \int x^{n} dx = \frac{x^{n+1}}{n+1} + C \quad x\neq -1

    Here you have n = -2 ...
    but can you show me the answer please geez
    Follow Math Help Forum on Facebook and Google+

  6. #6
    o_O
    o_O is offline
    Primero Espada
    o_O's Avatar
    Joined
    Mar 2008
    From
    Canada
    Posts
    1,407
    ??? You just simply apply what I told you and you're done.

    We are generally here to help you through a question. It's up to you to understand what's going on and figure how to reach the end by yourself. Why don't you actually do the work and we'll see if you did it correctly or not? "geez"
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. integration by substitution
    Posted in the Calculus Forum
    Replies: 2
    Last Post: May 3rd 2010, 11:12 PM
  2. Integration by Substitution Help
    Posted in the Calculus Forum
    Replies: 1
    Last Post: February 1st 2009, 08:28 PM
  3. integration by substitution xe^x^2
    Posted in the Calculus Forum
    Replies: 1
    Last Post: October 5th 2008, 10:48 PM
  4. integration by substitution
    Posted in the Calculus Forum
    Replies: 1
    Last Post: March 6th 2008, 05:22 PM
  5. integration by substitution
    Posted in the Calculus Forum
    Replies: 2
    Last Post: November 19th 2006, 03:46 PM

Search Tags


/mathhelpforum @mathhelpforum