The Best International Math Olympiad (IMO) Algebra Problem I've Ever Solved

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  • Опубліковано 27 лис 2024

КОМЕНТАРІ • 26

  • @ronbannon
    @ronbannon 4 дні тому +7

    Graphing the given equation will give you a line m+n-33=0 and a point (-33, -33). This is a very nice problem!

    • @drpkmath12345
      @drpkmath12345  2 дні тому

      Nice my friend haha. Thanks for sharing👍👍👍

  • @tsur.livney
    @tsur.livney 5 днів тому +6

    Brilliant!
    I solved it very differently:
    First i set a=33 for convenience and so the equation became:
    A^3 = m^3+n^3+3amn.
    I substituted a = m+n+delta on both sides, so i got:
    (m+n+delta)^3 = m^3 + n^3 + 3mn(m+n+delta).
    Opening the brackets and subtracting both sides by the lhs and rhs of the original equation, all terms left had delta in them so delta=0 derives the set of m+n=33 solutions.
    Dividing by delta we're left with a quadratic equation whose determinant is -3(m-n)^2, which eliminates all solutions where m is not equal to n.
    Now substituting m=n in our original equation, we are left with:
    A^3=2n^3+3an.
    Now using the same trick: setting this time a=delta-n, simplifying we get:
    Delta^2*(delta-3n) = 0.
    So either delta is 0 which implies a=-n=-m which gives the last solution, or a=2n=2m which means m+n=a which is already covered in previous solutions.
    Overall, for a general non zero value of a:
    Either m=n=-a - one solution,
    or m+n=a, which implies all solutions (i, a-i) where min(a,0)

    • @drpkmath12345
      @drpkmath12345  2 дні тому

      Thats really nice my friend haha👍👍👍 Nice method!

  • @adityavsx
    @adityavsx 5 днів тому +5

    you have a talent to explain complex sums so easily…gives me a lot of motiv:)

    • @MrGLA-zs8xt
      @MrGLA-zs8xt 4 дні тому

      I agree with you

    • @drpkmath12345
      @drpkmath12345  2 дні тому +1

      Wow thanks a lot for your compliment my friend👍👍👍

  • @alexkaralekas4060
    @alexkaralekas4060 5 днів тому +2

    Or just use from the start one of euler's identity a^3+b^3+c^3-3abc= {(a+b+c)[(a-b)^2+(b-c)^2+(c-a)^2]}/2
    For a=m b=n c=-33

    • @Min-cv7nt
      @Min-cv7nt 5 днів тому

      Isn't that vieta's formula?

    • @alexkaralekas4060
      @alexkaralekas4060 5 днів тому

      @Min-cv7nt i learned it as a factoring method for a^3+b^3+c^3 my book said it was from euler but I couldn't find it on the internet

    • @ronbannon
      @ronbannon 4 дні тому

      That is a most excellent idea! Thanks for pointing this out.

    • @drpkmath12345
      @drpkmath12345  2 дні тому

      Yes right haha. Thanks for sharing my friend👍👍👍

  • @iqtrainer
    @iqtrainer 3 дні тому +1

    Great work as always professor🎉

  • @mathnerd5647
    @mathnerd5647 3 дні тому +1

    This is such a nice video

  • @MrGLA-zs8xt
    @MrGLA-zs8xt 5 днів тому +2

    What a brilliant and nice video professor

  • @domedebali632
    @domedebali632 5 днів тому +1

    What a brilliant video

  • @Min-cv7nt
    @Min-cv7nt 5 днів тому +1

    You are the best professor

  • @redroach401
    @redroach401 5 днів тому +2

    Can you do ploynomial divison after you find the factor m+n-33 or no?