Results 1 to 10 of 10

Math Help - Expand and simplify

  1. #1
    Member
    Joined
    Jul 2008
    Posts
    212

    Expand and simplify

    a) (x+1/y)^2
    b) (x-(1/3y)+(2/5z))^2
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,970
    Thanks
    1011
    Quote Originally Posted by brumby_3 View Post
    a) (x+1/y)^2
    b) (x-(1/3y)+(2/5z))^2
    \left(x + \frac{1}{y}\right)^2 = \left(x + \frac{1}{y}\right)\left(x + \frac{1}{y}\right).

    FOIL it out.


    I can't read the second. Has it got \frac{1}{3y} and \frac{2}{5z}, or \frac{1}{3}y and \frac{2}{5}z?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Jul 2008
    Posts
    212
    Hi Prove it,
    It's the second combination.
    So for the first one would it be x^2 + (1/y)x + (1/y)x + (1/y)^2 or is it x^2 + (1/xy) + (1/xy) + (1/y)^2
    ???
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,970
    Thanks
    1011
    Quote Originally Posted by brumby_3 View Post
    Hi Prove it,
    It's the second combination.
    So for the first one would it be x^2 + (1/y)x + (1/y)x + (1/y)^2 or is it x^2 + (1/xy) + (1/xy) + (1/y)^2
    ???
    The first combination.

    And remember that x\left(\frac{1}{y}\right) = \frac{x}{y}.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Member
    Joined
    Jul 2008
    Posts
    212
    Cool, so my final answer for the first one is x^2 + (2x/y) + (1/y)^2
    Am I right?
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,970
    Thanks
    1011
    Quote Originally Posted by brumby_3 View Post
    Cool, so my final answer for the first one is x^2 + (2x/y) + (1/y)^2
    Am I right?
    Yes. But remember that \left(\frac{1}{y}\right)^2 = \frac{1}{y^2}.
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Newbie
    Joined
    Mar 2010
    Posts
    5

    Solution

    a) (x+1/y)^2

    (x+1/y)^2 = (x+1/y)(x+1/y)

    (x+1/y)(x+1/y)= x^2+x/y+x/y+1/y

    x^2+x/y+x/y+1/y= x^2+2x/y+1/y

    Answer= x^2+2x/y+1/y
    Follow Math Help Forum on Facebook and Google+

  8. #8
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,970
    Thanks
    1011
    Quote Originally Posted by Arcane10 View Post
    a) (x+1/y)^2

    (x+1/y)^2 = (x+1/y)(x+1/y)

    (x+1/y)(x+1/y)= x^2+x/y+x/y+1/y

    x^2+x/y+x/y+1/y= x^2+2x/y+1/y

    Answer= x^2+2x/y+1/y
    1. There was no need to post this, as the question had already been solved.

    2. If you're going to post a full solution, at least make sure you get it right...

    \left(x + \frac{1}{y}\right)^2 = x^2 + \frac{2x}{y} + \frac{1}{y\color{red}^2}.
    Follow Math Help Forum on Facebook and Google+

  9. #9
    Newbie
    Joined
    Mar 2010
    Posts
    5
    and it was right
    Follow Math Help Forum on Facebook and Google+

  10. #10
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,970
    Thanks
    1011
    No it wasn't.

    Reread my post, you'll notice something you missed.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Expand and simplify 5 - (2-x)^2
    Posted in the Algebra Forum
    Replies: 4
    Last Post: September 26th 2011, 07:03 AM
  2. Expand and simplify 1-(AB - C)^2
    Posted in the Algebra Forum
    Replies: 4
    Last Post: November 25th 2010, 11:46 AM
  3. expand and simplify
    Posted in the Algebra Forum
    Replies: 3
    Last Post: September 10th 2010, 09:20 AM
  4. How do I expand and simplify the following?
    Posted in the Algebra Forum
    Replies: 6
    Last Post: March 8th 2010, 11:01 AM
  5. Expand and simplify help?
    Posted in the Algebra Forum
    Replies: 6
    Last Post: October 30th 2009, 08:48 AM

Search Tags


/mathhelpforum @mathhelpforum