Results 1 to 5 of 5

Math Help - please do it completely plzzz

  1. #1
    Newbie
    Joined
    Jan 2008
    Posts
    19

    please do it completely plzzz

    (2x-2y-2z)^2
    solve above!I mean expand using sonme sort of formula
    plz dont joke me 4 such a questone I am a student of low level I mean low class oh junior class
    Last edited by Peacewanters007; January 3rd 2008 at 02:35 AM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member DivideBy0's Avatar
    Joined
    Mar 2007
    From
    Melbourne, Australia
    Posts
    432
    Hi Peacewanters2007!

    What exactly do you want to do with that? Do you need to expand it? Or is it part of an equation you need to solve?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member wingless's Avatar
    Joined
    Dec 2007
    From
    Istanbul
    Posts
    585
    (a + b + c)^2 = (a + b + c)(a + b + c) = a.a + a.b + a.c + b.a + b.b + b.c + c.a + c.b + c.c = a^2 + b^2 + c^2 + 2ab + 2ac + 2bc

    So, take a=2x, b=-2y, c=-2z,
    4x^2 + 4y^2 + 4z^2 - 8xy - 8xz + 8yz

    Or you could do this without using a formula,

    (2x - 2y - 2z)^2 = (2x - 2y - 2z)(2x - 2y - 2z) = 4x^2 - 4xy - 4xz -4xy + 4y^2 + 4yz - 4xz + 4yz + 4z^2 = 4x^2 + 4y^2 + 4z^2  - 8xy  - 8xz + 8yz
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,888
    Thanks
    326
    Awards
    1
    Quote Originally Posted by Peacewanters007 View Post
    (2x-2y-2z)^2
    solve above!I mean expand using sonme sort of formula
    plz dont joke me 4 such a questone I am a student of low level I mean low class oh junior class
    Perhaps you should look at it as
    (2x - 2y - 2z) = ((2x - 2y) - 2z)^2 = (2x - 2y)^2 - 2(2x - 2y)(2z) + (2z)^2
    which you should be able to expand on your own from here.

    -Dan
    Follow Math Help Forum on Facebook and Google+

  5. #5
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    or you could use the multinomial theorem

    (topsquark's method is perhaps easier, but you'll get a messy expression anyway)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Trig problem help plzzz
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: April 12th 2009, 08:56 AM
  2. graphing assignment help plzzz!!
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: March 31st 2009, 06:05 PM
  3. PLzzz Help!!!!!!!!!!!!!!-Skew?
    Posted in the Advanced Statistics Forum
    Replies: 4
    Last Post: January 9th 2009, 06:26 PM
  4. Urgently need help! If any1 can do this plzzz help! ><
    Posted in the Advanced Algebra Forum
    Replies: 6
    Last Post: April 8th 2008, 07:18 AM
  5. plzzz answer
    Posted in the Algebra Forum
    Replies: 2
    Last Post: January 6th 2008, 06:19 AM

Search Tags


/mathhelpforum @mathhelpforum