Results 1 to 3 of 3

Math Help - Simplifying Rational Expressions

  1. #1
    Newbie
    Joined
    Sep 2008
    From
    Innisfil, Ontario
    Posts
    16

    Simplifying Rational Expressions

    I'm doing my victory lap (Grade 13), and I need a credit in Advanced Functions.

    I'm already working my butt off to keep up with the review, but I feel that I need a solid foundation of these concepts before I can really excel in this course. So, If anybody could give me a hand...



    I looked at (x^2 - 1) as a difference of squares, and then multiplied each side by the other's denominator to achieve a common denominator.



    Then I canceled, and ended up with this:



    Collected like terms...



    Then, I thought - I'm way off track here. The answer is apparently



    I'm hoping someone can do the answer, and explain to me where I went wrong. I've tried it several times, but I'm just too rusty, I think. Thanks a million to whoever's up to the task!

    - Cameron
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Banned
    Joined
    Aug 2008
    Posts
    530
    [quote=Cam5;183971]I'm doing my victory lap (Grade 13), and I need a credit in Advanced Functions.

    I'm already working my butt off to keep up with the review, but I feel that I need a solid foundation of these concepts before I can really excel in this course. So, If anybody could give me a hand...

    your expression before cancelling; =\frac{4(x+1)(x-1) + 5(x-1)}{(x-1)(x-1)(x+1)}

    take common (x-1) from numerator, =\frac{(x-1)[4(x+1) + 5]}{(x-1)(x-1)(x+1)}

    You should cancel one (x-1) from both Numerator and denominator. After cancellation, you should have =\frac{4(x+1) + 5}{(x-1)(x+1)} =\frac{4x+9}{(x-1)(x+1)}

    See here the answer:

    =\frac{4}{x-1}+\frac{5}{x^2-1}

    =\frac{4}{x-1}+\frac{5}{(x-1)(x+1)}

    =\frac{4(x+1) + 5}{(x-1)(x+1)}

    =\frac{4x+4 + 5}{(x-1)(x+1)}

    =\frac{4x+9}{(x-1)(x+1)}
    Last edited by Shyam; September 8th 2008 at 01:51 PM.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2008
    From
    Innisfil, Ontario
    Posts
    16
    Thanks a lot Shyam! That clears it up for me.

    I'm still rusty on the factoring, as well, so that little gem didn't present itself to me right away, even when you worked it out for me.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. simplifying rational expressions!! ?
    Posted in the Algebra Forum
    Replies: 6
    Last Post: November 27th 2012, 06:19 AM
  2. Simplifying rational expressions 2
    Posted in the Algebra Forum
    Replies: 3
    Last Post: October 10th 2010, 02:44 PM
  3. Replies: 3
    Last Post: November 18th 2008, 12:50 PM
  4. simplifying rational expressions
    Posted in the Algebra Forum
    Replies: 1
    Last Post: September 16th 2007, 07:23 AM
  5. Simplifying rational expressions
    Posted in the Algebra Forum
    Replies: 1
    Last Post: April 1st 2006, 04:43 PM

Search Tags


/mathhelpforum @mathhelpforum