Results 1 to 7 of 7

Math Help - How to start?

  1. #1
    Newbie
    Joined
    Nov 2007
    Posts
    6

    How to start?

    Hi

    I have been scratching my head over this problem.

    Find s,t,u and v if s^2 + t^2 + u^2 + v^2 - st - tu -uv - v + 2/5 = 0

    Please help!

    gentsl
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    10,212
    Thanks
    419
    Awards
    1
    Quote Originally Posted by gentsl View Post
    Hi

    I have been scratching my head over this problem.

    Find s,t,u and v if s^2 + t^2 + u^2 + v^2 - st - tu -uv - v + 2/5 = 0

    Please help!

    gentsl
    Are s, t, u, and v integers or real numbers?

    -Dan
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Lord of certain Rings
    Isomorphism's Avatar
    Joined
    Dec 2007
    From
    IISc, Bangalore
    Posts
    1,465
    Thanks
    6
    Quote Originally Posted by gentsl View Post
    Hi

    I have been scratching my head over this problem.

    Find s,t,u and v if s^2 + t^2 + u^2 + v^2 - st - tu -uv - v + 2/5 = 0

    Please help!
    gentsl
    I too have been scratching my head over this problem.
    Are you using parenthesis correctly?
    It mostly looks like a candidate for the following manipulations:

    2s^2 + 2t^2 + 2u^2 + 2v^2 - 2st - 2tu -2uv - 2v + \frac45 = 0
    s^2 + (s-t)^2 + (t-u)^2 + (u-v)^2 + (v - 1)^2 - \frac15 = 0

    Are s, t, u, and v integers or real numbers
    How can integer solutions exist if the last thing is a fraction?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    10,212
    Thanks
    419
    Awards
    1
    Quote Originally Posted by Isomorphism View Post
    How can integer solutions exist if the last thing is a fraction?
    (Ahem!)

    -Dan
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Nov 2007
    Posts
    6
    It is not stated if they are integers or real numbers.

    Thanks Isomorphism for pointing that out. Just curious, if any of you went all the way to get s,t,u and v.

    By the way, I wasn't notified by email of replies to this thread. I wonder why.

    gentsl
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by gentsl View Post
    It is not stated if they are integers or real numbers.

    Thanks Isomorphism for pointing that out. Just curious, if any of you went all the way to get s,t,u and v.

    By the way, I wasn't notified by email of replies to this thread. I wonder why.

    gentsl
    Isomorphism has done most of the hard work ...... Perhaps the following will keep the ball rolling for you:

    Quote Originally Posted by Isomorphism View Post
    s^2 + (s-t)^2 + (t-u)^2 + (u-v)^2 + (v - 1)^2 - \frac15 = 0
    \therefore s^2 + (s-t)^2 + (t-u)^2 + (u-v)^2 + (v - 1)^2 = \frac{1}{5}

    So obviously (why?) each term on the left hand side has to be less than 1/5. This leads to a system of simultaneous inequalities ......
    Last edited by mr fantastic; January 7th 2008 at 03:09 PM.
    Follow Math Help Forum on Facebook and Google+

  7. #7
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by gentsl View Post
    By the way, I wasn't notified by email of replies to this thread. I wonder why.
    that's strange. check your user control panel. go to "edit options" and ensure that all the relevant checks and settings are set in the message and notification section.

    otherwise, check to make sure you are subscribed to this thread (you should be automatically since you created it, but you never know...). click on "thread tools" and if you see "subscribe to this thread" in the drop down menu, click it

    if all that doesn't work, send a PM to one of the administrators
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Can't start
    Posted in the Trigonometry Forum
    Replies: 9
    Last Post: January 10th 2010, 07:34 AM
  2. Please help me start this
    Posted in the Algebra Forum
    Replies: 1
    Last Post: November 8th 2009, 06:40 PM
  3. Don't know where to start...
    Posted in the Advanced Statistics Forum
    Replies: 6
    Last Post: February 15th 2009, 02:57 AM
  4. can someone help me start this?
    Posted in the Algebra Forum
    Replies: 1
    Last Post: September 5th 2008, 01:21 AM
  5. How do I start
    Posted in the Advanced Algebra Forum
    Replies: 1
    Last Post: September 17th 2005, 10:32 PM

Search Tags


/mathhelpforum @mathhelpforum