SQL Server Performance

Great Mathematics...

Discussion in 'The Lighter Side of Being a DBA' started by ghemant, Feb 9, 2006.

  1. ghemant Moderator

    Long ago, a mathematician used to cheat people. Once
    he borrowed
    Rs.4000/- from a rich man. After a few days, he
    borrowed Rs.2000/- from the same man.

    Many days passed, the mathematician did not return the
    money to the rich man. The rich man went to the
    mathematician and asked to return the money.

    But to his great surprise, the mathematician replied
    that there is no
    need to pay the debt.

    "See here, friend" said the mathematician " the sum of
    4000 and 2000 is equal to
    zero, so I do not have any balance to pay".

    The rich man took the matter to the court. When the
    judge came to know
    this, he was astonished. He asked the mathematician to
    prove that sum of 4000 and 2000 is zero, and not 6000.

    The Clever mathematician agreed. He said:

    let a == 4000, b == 2000 and c == 6000

    a + b == c

    Multiply both sides by a + b

    (a + b) (a + b ) == c (a + b)

    a*a + ab + ba + ! b*b == ca + cb

    a*a + ab - ca == cb - b*b - ba

    a( a + b -c) == -b(b + a - c)

    so a == - b

    a + b == 0

    Hence 4000 + 2000 = 0............


    Hemantgiri S. Goswami
    ghemant@gmail.com
    "Humans don't have Caliber to PASS TIME , Time it self Pass or Fail Humans" - by Hemantgiri S. Goswami
  2. ranjitjain New Member

    I Needed to learn about this kind of mathematics[<img src='/community/emoticons/emotion-2.gif' alt=':D' />][<img src='/community/emoticons/emotion-2.gif' alt=':D' />]
  3. FrankKalis Moderator

    I think I'm going to tell that to my bank next time. [<img src='/community/emoticons/emotion-2.gif' alt=':D' />]<br /><br />--<br />Frank Kalis<br />Microsoft SQL Server MVP<br /<a target="_blank" href=http://www.insidesql.de>http://www.insidesql.de</a><br />Heute schon gebloggt?<a target="_blank" href=http://www.insidesql.de/blogs>http://www.insidesql.de/blogs</a><br />
  4. mmarovic Active Member

    mssql server would report divide by zero exception [<img src='/community/emoticons/emotion-1.gif' alt=':)' />]
  5. Adriaan New Member

    I thought (a+b)(a+b) = a*a + 2ab + b*b - but I'm not really good at maths.

    a*a + 2ab + b*b = ca + cb

    4*4 + 2*4*6 + 6*6 = 6*2 + 6*4

    16 + 48 + 36 = 12 + 24

    100 = 36 - nah, I don't think so.
  6. FrankKalis Moderator

    Well, a*a + 2ab + b*b is certainly equivalent to a*a + ab + ba + b*b. But you have some typos in your formula. Anyway, think about Mirko's comment. [<img src='/community/emoticons/emotion-1.gif' alt=':)' />]<br /><br /><br />--<br />Frank Kalis<br />Microsoft SQL Server MVP<br /<a target="_blank" href=http://www.insidesql.de>http://www.insidesql.de</a><br />Heute schon gebloggt?<a target="_blank" href=http://www.insidesql.de/blogs>http://www.insidesql.de/blogs</a><br />
  7. Adriaan New Member

    Like I said, I wasn't really good at maths.

    Not sure if this is equivalent to (a+b)(a+b) - someone care to explain this?

    a*a + ab + ba + ! b*b
  8. FrankKalis Moderator

  9. mmarovic Active Member

    The problem is here: a( a + b -c) == -b(b + a - c)
    a+b-c = 0 so any x * 0 = y * 0, so it is not equivalent to x = y.
    The rule is: t <> 0 => (x*t = y*t <=> x=y)


    Adriaan: !b*b should be b*b
  10. FrankKalis Moderator

    q.e.d [<img src='/community/emoticons/emotion-1.gif' alt=':)' />]<br /><br />--<br />Frank Kalis<br />Microsoft SQL Server MVP<br /<a target="_blank" href=http://www.insidesql.de>http://www.insidesql.de</a><br />Heute schon gebloggt?<a target="_blank" href=http://www.insidesql.de/blogs>http://www.insidesql.de/blogs</a><br />
  11. mmarovic Active Member

    Frank, are you mathematician too? [<img src='/community/emoticons/emotion-1.gif' alt=':)' />]
  12. FrankKalis Moderator

    Not by profession. Actually I'm more into Financial Mathematics and Statistics. But I love such puzzles. [<img src='/community/emoticons/emotion-1.gif' alt=':)' />]<br /><br />Are you a mathematician?<br /><br />--<br />Frank Kalis<br />Microsoft SQL Server MVP<br /<a target="_blank" href=http://www.insidesql.de>http://www.insidesql.de</a><br />Heute schon gebloggt?<a target="_blank" href=http://www.insidesql.de/blogs>http://www.insidesql.de/blogs</a><br />
  13. Adriaan New Member

    Phew - I had to dig pretty deep into my memory banks here! One can take only so much maths on any given day. Or another.
  14. mmarovic Active Member

    Sort of. I graduated computer science on faculty of mathematics. We actually studied mathematic much more then computer science. However, after graduation I didn't have much opportunity to apply my math knowledge, so right now I don't remember much of what I've learned for years [<img src='/community/emoticons/emotion-6.gif' alt=':(' />]
  15. Madhivanan Moderator

    As a+b=c
    a + b -c=0
    So you cant divide 0 on two sides of the equation

    Madhivanan

    Failing to plan is Planning to fail
  16. Luis Martin Moderator

    Funy once on vacation.

    Of course you can divede by 0 in any case.
    That is a good example why.

    So when you simplify (a + b -c) whit (b + a - c) your are diveding by 0, and that is the joke.


    Luis Martin
    Moderator
    SQL-Server-Performance.com

    Although nature commences with reason and ends in experience it is necessary for us to do the opposite, that is to commence with experience and from this to proceed to investigate the reason.
    Leonardo Da Vinci

    Nunca esperes el reconocimiento de tus hijos, eso ocurrirá luego de tu muerte


    All postings are provided “AS IS” with no warranties for accuracy.



  17. Adriaan New Member

    I got the joke - I think - a few posts up from here already.

    The fun bit is that he's adding the (a+b) on both sides., then deduces both sides to 0, which isn't the object of the whole excercise anyway. Yeah, great fun - ah um.
  18. Madhivanan Moderator

    Mathematician is correct if this is correct

    1*0=0
    2*0=0
    1*0=2*0
    1=2


    Madhivanan

    Failing to plan is Planning to fail
  19. FrankKalis Moderator

    [<img src='/community/emoticons/emotion-5.gif' alt=';)' />]<br /><br />--<br />Frank Kalis<br />Microsoft SQL Server MVP<br /<a target="_blank" href=http://www.insidesql.de>http://www.insidesql.de</a><br />Heute schon gebloggt?<a target="_blank" href=http://www.insidesql.de/blogs>http://www.insidesql.de/blogs</a><br />

Share This Page