You're Ready for a Maths Olympiad if you Can Solve this one...

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  • เผยแพร่เมื่อ 29 มิ.ย. 2023
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    The video: • I'm Ruining my Entire ...
    Today we solve a diophantine equation x+xy+y=55 using two very different, but awesome attempts :D Enjoy :3
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ความคิดเห็น • 123

  • @PapaFlammy69
    @PapaFlammy69  11 หลายเดือนก่อน +9

    *_big bet_*
    Check out Brilliant to get a 30 day free trial of awesomeness! =D brilliant.org/FlammableMaths
    Interested in my Anime Figurines? www.kleinanzeigen.de/s-bestandsliste.html?userId=85111216
    Support my channel and become a Patron! =) www.patreon.com/mathable
    The video: th-cam.com/video/uWWcGHUN3QE/w-d-xo.html

    • @DreamyyArt
      @DreamyyArt 11 หลายเดือนก่อน

      CHALLENGE ACCEPTED (I'm a 6th grader lmaoo9

    • @DreamyyArt
      @DreamyyArt 11 หลายเดือนก่อน

      IM ALMOST THERE (getting 53.4)

    • @DreamyyArt
      @DreamyyArt 11 หลายเดือนก่อน

      WOOOOOOOO IM MATHING AN ANSWER IS 13 AND 3 🎉🎉🎉🎉🎉🎉🎉🎉 IM JUST GRADE 6

    • @DreamyyArt
      @DreamyyArt 11 หลายเดือนก่อน

      I broke it down using tree method and slowly offsetting my 2 numbers

    • @oumery3285
      @oumery3285 11 หลายเดือนก่อน

      Wht's that on Ur t-shirt ?

  • @MathIguess
    @MathIguess 11 หลายเดือนก่อน +343

    y=0, x=55. Where's my million dollars??

    • @shizensuu
      @shizensuu 11 หลายเดือนก่อน +11

      genius

    • @anonymoushere7786
      @anonymoushere7786 11 หลายเดือนก่อน +7

      💀

    • @sparshjain27
      @sparshjain27 11 หลายเดือนก่อน +55

      x = 0 , y = 55. Where's mine

    • @cxpKSip
      @cxpKSip 11 หลายเดือนก่อน +10

      $x=n, y=\frac{55-n}{n+1}$ solves it, $\forall x\in\mathbb{Z}\setminus\{-1\}$. You didn't solve it hard enough.
      Of these: x=0 (y=55),1 (y=27),3 (y=13), 6 (y=7),-2 (y=-57),-3 (y=-29),-5 (y=-15),-8 (y=-9) are the only distinct solutions where |x|

    • @djfghjif
      @djfghjif 11 หลายเดือนก่อน

      ​@@cxpKSip🤓

  • @yongkhin7874
    @yongkhin7874 10 หลายเดือนก่อน +8

    The method of "completing the rectangle" is taught in the Singapore's mathematics curriculum not to solve diophantine equations but to factorise quadratice equations.

  • @MathIguess
    @MathIguess 11 หลายเดือนก่อน +26

    Haven't done Diophantine equations in a while so this was really fun and refreshing to watch :)

  • @mr.inhuman7932
    @mr.inhuman7932 11 หลายเดือนก่อน +13

    Okkkk I admit the visualization was actually really really good.
    Also the sponsor-segway was just butter smooth.

    • @ianthehunter3532
      @ianthehunter3532 11 หลายเดือนก่อน +2

      Segway is a trademark brand name for an electric vehicle with two wheels. The rider stands on a base between the wheels and holds onto a bar at waist height.

  • @TapiokaOishii
    @TapiokaOishii 11 หลายเดือนก่อน +5

    I tried myself before watching the video, and the way i solved this was similar:
    x + xy + y = 55
    x(y + 1) + y = 55
    Let a = y + 1, so y = a - 1:
    x * a + a - 1 = 55
    ax + a = 56
    a(x + 1) = 56
    Let b = x + 1:
    ab = (2^3) * 7
    the values of a and b that satisfy the equation are all the divisors of (2^3) * 7, thus:
    a or b = 1, 2, 4, 7, 8, 14, 28, 56
    To find x and y we just need to substract 1 to the values of b and a, so:
    x or y = 0, 1, 3, 6, 7, 13, 27, 55.

  • @aadhaarmurty1180
    @aadhaarmurty1180 11 หลายเดือนก่อน +41

    Mitochondria are the powerhouse of the cell. Also, the phrases 'this blows' and 'this sucks' are both opposite and identical at the same time.
    Non sequitur.

    • @MathIguess
      @MathIguess 11 หลายเดือนก่อน +5

      Flammable = inflammable, confirmed

  • @denizgoksu9868
    @denizgoksu9868 11 หลายเดือนก่อน +6

    Alternative title: Why succ is my favorite function

  • @lupen8095
    @lupen8095 11 หลายเดือนก่อน +23

    The only math teacher who greets everyone with Satanism. This is peak math content

  • @m.h.6470
    @m.h.6470 4 หลายเดือนก่อน

    Without doing a lot of math:
    Since it is the sum of two numbers plus the product of two numbers and the answer is an integer, the two numbers also have to be integers.
    Also either both numbers are positive or both are negative, otherwise the result would also be negative.
    Also neither number can be -1, as it would cause the equation to collapse to -1 = 55, which is obviously not correct.
    Some valid results (not all of the valid ones):
    0 and 55 → obvious, as the 2 of the 3 terms become 0 and the last one has to be 55
    1 and 27 → not as obvious, the equation becomes 1 + 1*27 + 27 = 1 + 2*27 = 1+ 54 = 55
    6 and 7 → splitting 55 into the product and the sum of roughly equal numbers, the numbers have to be somewhere close to 7, as 7² + 2*7 = 49 + 14 = 63
    Seeing, that I found 6 solutions, with all positive numbers, there has to be at least double, probably triple, that.

  • @cooldawg2009
    @cooldawg2009 10 หลายเดือนก่อน

    Dude, this is so cool!

  • @hirsh7542
    @hirsh7542 11 หลายเดือนก่อน +15

    I didn't realize you could factor it at the start, so I just did x+y(x+1)=55 because why not, at which point it becomes more obvious that you can add 1 to both sides and factor. Really cool visualization!

  • @mr.boloso8296
    @mr.boloso8296 11 หลายเดือนก่อน +3

    I came up with y = (55 - x) / (x + 1), then I noticed it is a function and started testing values
    f(0) = 55 ==> x = 0; y = 55;
    f(1) = 27 ==> x = 1; y = 27;
    ...
    It is a bit dumb way to solve it, but hopefully I've got smarter with Flamys sAtAnIç explanation. Thanks!

    • @richardbloemenkamp8532
      @richardbloemenkamp8532 11 หลายเดือนก่อน

      This is called the programmer's method. You don't have to think and still you have the fastest answer assuming you have your computer already booted up in front of you with some simple language like BASIC, Python, Matlab, etc.

    • @himanbam
      @himanbam 11 หลายเดือนก่อน

      ​@@richardbloemenkamp8532wrong. The fastest answer is saying y=0 x=55.

    • @richardbloemenkamp8532
      @richardbloemenkamp8532 11 หลายเดือนก่อน

      @@himanbam True, but that is an incomplete answer if the question is to find all the integer solutions to the equation. If the question is to find an integer solution then I agree of course.

    • @alexdukec.7551
      @alexdukec.7551 5 หลายเดือนก่อน

      I took the same approach, but I took it one step further. When the rquation looks like y = (55 - x) / (x + 1), you can take the one out of the right side, turning a nasty looking rational into an easy-to-understand transformation of the function f(x) = 1 / x. When you take the one out, you end up with y = ( 56 / (x + 1) ) - 1. From there, it's easier to see how finding integer solutions is related to the prime factorization of 56, and then find the solutions

  • @markgibbs8782
    @markgibbs8782 11 หลายเดือนก่อน

    Complete the rectangle. Very cool !

  • @mr.inhuman7932
    @mr.inhuman7932 11 หลายเดือนก่อน +3

    Wait... you can use Brilliant for Chemistry too?!
    Well... I think I'ma check it out.

  • @melchiortod29
    @melchiortod29 11 หลายเดือนก่อน +1

    The way i did it: x(1+y) +y=55 => x= 55-y / (1+y) =>( 56 - (1+y) )/(1+y) = 56/(1+y) -1 and then you just gotta impose 56/(1+y) to be integer

  • @trelligan42
    @trelligan42 11 หลายเดือนก่อน

    Awesome visual method, thank you. I will never forget this. #FeedTheAlgorithm

  • @ARCHIMOOD
    @ARCHIMOOD 11 หลายเดือนก่อน +5

    I was working on this before and one of my best results was
    x+xy+y=n is equivalent to
    (2x+y+1)^2=(y-1)^2 + (2x)^2 + (2√n)^2
    in your case
    (2x+y+1)^2= (y-1)^2 + (2x)^2 + 220
    from the Pythagorean diagonal in 3D
    And i stopped right there i couldn't devlope the results to something useful 😅
    Maybe it helps👍

    • @mob6804
      @mob6804 11 หลายเดือนก่อน

      Unironic question: Wouldn't x= 15 y= 2.5 achieve the same effect? If you were to sub those numbers into the formula you'd get 55..

    • @gameplaydecrianca
      @gameplaydecrianca 10 หลายเดือนก่อน

      ​@@mob6804the question asks the integer solutions, there are infinitely many rational ones

  • @mr.inhuman7932
    @mr.inhuman7932 11 หลายเดือนก่อน +3

    The equation on his shirt is actually based.
    Tau > Pi. And that's a fact.

    • @livedandletdie
      @livedandletdie 11 หลายเดือนก่อน

      ⊤(τ>π)∴⊤(τ>π)∵⊤(τ>π) Is logically sound, because it's logically sound... Tautology for the sake of Tautology is still Tautology.

  • @user-lk3js4zx1o
    @user-lk3js4zx1o 6 หลายเดือนก่อน

    nice one ty

  • @howdoi_yt
    @howdoi_yt 11 หลายเดือนก่อน

    that satenic intro was gold

  • @fire5281
    @fire5281 11 หลายเดือนก่อน +5

    5 mins after he uploaded
    the moment I saw x + xy + y = 55 I instantly thought of this: xy + x + y + 1 = (x+1)(y+1)
    yeah as you can guess from the original equation, we have (x+1)(y+1) = 56 (here we add 1 to both sides)
    if you are looking for x and y in forms of integers, well the rest of the problem is pretty self-explanatory
    56 = 1.56 = 2.28 = 4.14 = 8.7 (in this case we're looking for the values of x + 1 and y + 1 , which applies for both pairs of (x ; y) and (y ; x) as they play the same role in the equation regardless of the order of x and y)

    • @jevinliu4658
      @jevinliu4658 11 หลายเดือนก่อน +1

      I mean, it didn't even take me minutes. It took me seconds

    • @fire5281
      @fire5281 11 หลายเดือนก่อน +2

      @@jevinliu4658 I commented this after he uploaded 5 mins, didn't even watch the video
      maybe I didn't state it clearly enough that I was very early but whatever

  • @anotherpersononplanetearth3936
    @anotherpersononplanetearth3936 11 หลายเดือนก่อน

    I was only able to get one solution from this (with the exception of x=0 and y=55), x=27 and y=1, because I got lazy.
    I got it by doing X + xy + y = 55, then rewriting that as x + xy = 55 -y, then I divided both sides by y to get this x/y +x =55/y - y/y, then I noticed that -y/y would give me -1 for a constant, so next up was (x/y)+x = 55/y - 1, then I multiplied both sides by y, giving x + xy = 55-1, which became, x+ xy = 54.
    I concluded since I removed y and 55 became 54, y had to equal 1.
    So, I plugged y into the equation I simplified the starting equation to, x+x(1)=54, then I got 2x= 54, and resultingly attained x=27.
    Then I tested the results and got 27 + 27(1) + 1 = 27 + 27 + 1 = 27 + 28 = 40 + 15 = 55.

    • @zunaidparker
      @zunaidparker 11 หลายเดือนก่อน +1

      Can you spot where you made a mistake? Hint: your first step you divided by y. Your second step you multiplied by y, so you should have just got back to the original equation without having developed anything new.

    • @anotherpersononplanetearth3936
      @anotherpersononplanetearth3936 11 หลายเดือนก่อน +1

      @@zunaidparker Ah! I just caught onto it now that you mentioned it, thanks!

  • @Blue-ik8ij
    @Blue-ik8ij 11 หลายเดือนก่อน +1

    It's called the Simon's Favorite Factoring Trick. Man it takes me back to those olympiad days😌

    • @Nylspider
      @Nylspider 11 หลายเดือนก่อน

      Blast from the AoPS past

  • @surajitnaskar46
    @surajitnaskar46 11 หลายเดือนก่อน +6

    X is 6 and y is 7...very simple

  • @quatsch95
    @quatsch95 5 หลายเดือนก่อน +1

    I found 16 solutions (if x and y are integers), let me know if I’m wrong! :D
    x = 0, y = 55
    x = 1, y = 27
    x = 3, y = 13
    x = 6, y = 7
    x = 7, y = 6
    x = 13, y = 3
    x = 27, y = 1
    x = 55, y = 0
    x = -2, y = -57
    x = -3, y = -29
    x = -5, y = -15
    x = -8, y =-9
    x = -9, y = -8
    x = -15, y = -5
    x = -29, y = -3
    x = -57, y = -2

  • @juandavidrodriguezcastillo9190
    @juandavidrodriguezcastillo9190 11 หลายเดือนก่อน

    Thanks from colombia papa flammable maths

  • @cxpKSip
    @cxpKSip 11 หลายเดือนก่อน +1

    $x=n, y=\frac{55-n}{n+1}$ solves it, $\forall x\in\mathbb{Z}\setminus{-1}$. This comes from taking various integer inputs for x and then working out what y would have to be for that to equal 55. I guess what I did was this, if I am to put this on an exam:
    Suppose |x|

  • @LeaderTerachad
    @LeaderTerachad 11 หลายเดือนก่อน

    Thanks for video I was able to do this

  • @JoeBob79569
    @JoeBob79569 11 หลายเดือนก่อน

    Sounds like a lot of commenters here just solved the equation and commented before watching the rest of the video, and those guys missed out, big time, because the visual solution given is really elegant.
    And also it feels like my brain has expanded a little bit after watching it.

  • @FE2E00
    @FE2E00 11 หลายเดือนก่อน

    Saw the thumbnail and brute forced 6 and 7 in my head, but your way is cool too, maybe I'll watch it later

  • @Maths_3.1415
    @Maths_3.1415 11 หลายเดือนก่อน +1

    0:05 lol

  • @psikoexe
    @psikoexe 11 หลายเดือนก่อน

    Man you need to make some fresh videos on diophantine equations mod and such... I am so out of touch from these things for over an year now... I t would be fun to go to basic math for a while. Thanks papa flammy

  • @GreenMeansGOF
    @GreenMeansGOF 11 หลายเดือนก่อน +1

    Simon says: Add 1 to both sides.

  • @evelinastanchovska4171
    @evelinastanchovska4171 9 หลายเดือนก่อน

    Finally you wear a t-shirt that has a correct equatiin

  • @tgx3529
    @tgx3529 7 หลายเดือนก่อน

    I suppose, that x,y are natural numbers , no zero.
    If x= 2n & y=2k then Is there the contradiction.
    For x=2n, y=2k+1 se get also contradiction of type z+2zp+p=3
    Only x=2n+1 And y=2k+1 Is possible
    I take x=1;3;5;7.....
    Your solution Is nice.

  • @yesnt1918
    @yesnt1918 11 หลายเดือนก่อน

    Just make a shifted hyperbola to (-1,-1) and you will get your points

  • @toaster4693
    @toaster4693 11 หลายเดือนก่อน +5

    I've always been keen to take the algebraic approach to everything, but after teaching others I've started to recognize the importance of thinking graphically and geometrically and how it can really simplify problems and improve understanding, like you've shown with completing the rectangle. Want to solve x^2 > x? Old me: Subtract x, factor out x, solve x(x-1) = 0 and check intervals to see where x(x-1) > 0. New me: WTF are you doing fool, just look at the graph and see where the parabola is above the line lol.

    • @xXJ4FARGAMERXx
      @xXJ4FARGAMERXx 11 หลายเดือนก่อน

      Squaring usually gives bigger numbers, except fractions, they give smaller numbers when squared. So my intuition based guess for when x² > x is whenever x > 1 (if it's 1 squaring would be equal)
      Edit: I forgot about negative numbers. Squaring a negative always results in a positive, so x < 0 is also another part of the solution. So the full solution is (∞, 0) ∪ (1, ∞)

  • @CassieAngelica
    @CassieAngelica 11 หลายเดือนก่อน

    Challenge Accepted.

  • @lgooch
    @lgooch 11 หลายเดือนก่อน +1

    Disclaimer: if you can solve this you are in the 100% percentile within the olympiad community, this is SFFT

    • @user-fc7rp7gf7i
      @user-fc7rp7gf7i 5 หลายเดือนก่อน

      Real, just factor x or y then add 1 both sides

  • @iloveblender8999
    @iloveblender8999 10 หลายเดือนก่อน

    Ok, it took me a minute to realise, that we just needed to use some distributivity. That is why practice is important.

    • @iloveblender8999
      @iloveblender8999 10 หลายเดือนก่อน

      Ok, integer solutions, now I have to look at the problem again.

    • @iloveblender8999
      @iloveblender8999 10 หลายเดือนก่อน

      ok natural number solutions can be bruteforced, you only have to check 55 numbers, if they are integers.

  • @user-jy8bv9ke3j
    @user-jy8bv9ke3j 8 หลายเดือนก่อน

    Why sometimes chalk scratches on board

  • @bwhaz
    @bwhaz 11 หลายเดือนก่อน

    Lol, so I saw the thumbnail and grabbed pen and paper. Ended up with y = (55 - x) / (x + 1) . "leave the solving for all rational values as an exercise for the reader" helped explain why we didn't just hop into that and, instead, did the FOIL route lol. Makes sense, and you got the integer components; I guess? I dunno, there wasn't any thing else that I saw which led me to want to find out particular things about the thing besides figure out what X and Y were... And I found out what Y is when we pick an X so... I am just watching to learn Satanism, I guess.

    • @ethanbottomley-mason8447
      @ethanbottomley-mason8447 11 หลายเดือนก่อน +1

      Once you have y = (55 - x) / (x+1), you then want x to appear only in the denominator, so you remove the x from the top by adding and subtracting 1, like so: y = -1 + (55 - x + x + 1)/(x+1) = -1 + 56/(x+1), then you have exactly what you get in the video.

  • @animatnetic2545
    @animatnetic2545 11 หลายเดือนก่อน

    No one:
    Greeks when they have to solve an equation:

  • @johangonzalez4894
    @johangonzalez4894 11 หลายเดือนก่อน

    x+xy+y=55
    x(y+1)+y=55
    x(y+1)+y+1=55+1
    (x+1)(y+1)=56
    56=1*56=2*28=4*14=7*8
    WLOG take x

  • @inyobill
    @inyobill 7 หลายเดือนก่อน

    My secret friend is better than your secret friend.

  • @iamthekittycat
    @iamthekittycat 5 หลายเดือนก่อน

    i factored to (x+1)(y+1)

  • @mlloser8318
    @mlloser8318 11 หลายเดือนก่อน +1

    6,7 or 3,13 or 1,27

  • @Buenofresser
    @Buenofresser 11 หลายเดือนก่อน +1

    Schauen deine Schüler deine Videos und falls ja, sprechen die dich dann zb auf neue Videos an oder so?^^

  • @avinashbabut.n4123
    @avinashbabut.n4123 11 หลายเดือนก่อน

    13:11 Forgot 'from brilliant'?

  • @xthomas7621
    @xthomas7621 11 หลายเดือนก่อน

    Wtf is the start of this omg u r ceazy
    But more seriously i forgot how to do this kind of problem, agh

  • @umerhussain3855
    @umerhussain3855 11 หลายเดือนก่อน

    Bro I got x=335 and y= -5/6 and when I plugged it in I got 55.

  • @LawatheMEid
    @LawatheMEid 11 หลายเดือนก่อน

    X & y both odd numbers or one odd the other even.
    Consider x=y then both are odd .. the solution between 7 and 5 .. both did not solve the equation .. so it is 6 and 5 or 6 and 7 which it is.

  • @leob69
    @leob69 10 หลายเดือนก่อน

    easy, x=i and y=27-28i

  • @person-fy8kd
    @person-fy8kd 11 หลายเดือนก่อน +1

    Welcome satin the founder of I

  • @MelodicHarmonyy
    @MelodicHarmonyy 11 หลายเดือนก่อน

    I got that x= 6 and y=7 due to x+y=55-x. Only 12 but am i ready

    • @EscudosdeTimes
      @EscudosdeTimes 9 หลายเดือนก่อน

      Thtat is exactly me

  • @Morax___
    @Morax___ 11 หลายเดือนก่อน

    6,7

  • @kquat7899
    @kquat7899 11 หลายเดือนก่อน +1

    Tau's becoming a thing,

  • @sumanjangid1250
    @sumanjangid1250 3 หลายเดือนก่อน

    The equation on your t shirt is wrong!

  • @MohamedBenamer940
    @MohamedBenamer940 11 หลายเดือนก่อน

    x = -5, y = -15

  • @fleroviux
    @fleroviux 11 หลายเดือนก่อน

    I tried to solve this myself before watching the video and came up with the same visual method to factor it since my instinct was to try visualize the equation as an area.
    From there on I rearranged the equation to express **x** in terms of **y** :
    (x + 1) * (y + 1) = 56
    x + 1 = 56 / (y + 1)
    x = 56 / (y + 1) - 1
    Then I realized that the only way **x** could be integer is if **(y + 1)** divides 56.
    The positive integers that divide 56 are its prime factors (1, 2, 7) and all the products

    • @bunnygod3948
      @bunnygod3948 11 หลายเดือนก่อน

      Gotta be the best solution I've seen so far, well done

  • @EscudosdeTimes
    @EscudosdeTimes 9 หลายเดือนก่อน

    x=6 y=7
    Where's my invitation?

  • @omidrezamirhosseini6398
    @omidrezamirhosseini6398 10 หลายเดือนก่อน

    i solved it

  • @camicus-3249
    @camicus-3249 11 หลายเดือนก่อน

    brute force best method

  • @rafiihsanalfathin9479
    @rafiihsanalfathin9479 11 หลายเดือนก่อน

    This is a basic number theory problem, what is the deal?

  • @AntonisK27
    @AntonisK27 11 หลายเดือนก่อน

    Already solved it 😈 (I am lying)

  • @Savedon-131
    @Savedon-131 11 หลายเดือนก่อน

    B I G B E T

  • @GradientAscent_
    @GradientAscent_ 11 หลายเดือนก่อน +1

    What is this intro bro💀

  • @Wielorybkek
    @Wielorybkek 11 หลายเดือนก่อน +2

    I have found (1, 27), (3, 13), (6, 7) pretty quickly by guessing. :p
    Edit: of course I missed (0, 55), who would count 0 as a natural number anyway?

  • @alexchan4226
    @alexchan4226 11 หลายเดือนก่อน

    Sorry!

  • @lucasf.v.n.4197
    @lucasf.v.n.4197 9 หลายเดือนก่อน

    my hyperbolic cosine and sine solution doesn't work, since u're only considering integers; u should swap x and y by a and b in the thumbnail, u deceived me u brat!

  • @alberteinstein3612
    @alberteinstein3612 11 หลายเดือนก่อน +1

    Your shirt bothers me

    • @leob69
      @leob69 10 หลายเดือนก่อน

      me too

  • @tszhanglau5747
    @tszhanglau5747 11 หลายเดือนก่อน

    Succ(x)Succ(y)=Succ(55)

    • @richardbloemenkamp8532
      @richardbloemenkamp8532 11 หลายเดือนก่อน

      A very succ says full simplification indeed. I hope it won't lead to any off-by-one errors.