Calculating π by hand

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  • čas přidán 12. 03. 2016
  • For Pi Day 2016 I tried to calculate π by hand, using an infinite series. It goes ok.
    Before you even start:
    - Yes, I know π Day requites writing the date MM/DD. By objective measures: the wrong way. I don't care. My love of π is stronger.
    - My opinion of Tau is a matter of public record: • Tau vs Pi Smackdown - ...
    CORRECTIONS:
    - At 17:23 it should be π/4 not 1/π. That was contamination from the next graphic. (First spotted by Najeeb Sheikh and Jake Trookman.)
    Check out y-cruncher:
    www.numberworld.org/y-cruncher...
    Calculating pi by weighing a circle:
    • Calculating pi by weig...
    Calculating pi with a pendulum:
    • Calculating pi with a ...
    Music by Howard Carter
    Design by Simon Wright
    MATT PARKER: Stand-up Mathematician
    Website: standupmaths.com/
    New book: makeanddo4D.com/
    Nerdy maths toys: mathsgear.co.uk/
  • Zábava

Komentáře • 3,1K

  • @FourthDerivative
    @FourthDerivative Před 8 lety +6438

    This is what I thought mathematicians did for a living when I was a kid. Just adding and subtracting giant lists of numbers all day long.

    • @FlyingPiper13
      @FlyingPiper13 Před 8 lety +416

      +FourthDerivative Haha, yeah, I used to think math was something like that too. But it's a heck of a lot more beautiful than that, isn't it.

    • @remo4644
      @remo4644 Před 8 lety +151

      +FlyingPiper13 No, it's not

    • @nightangel7239
      @nightangel7239 Před 7 lety +169

      And he only passed by relying on the age-old method, "Just memorize the formulas and substitute, don't think".

    • @Kupkaik
      @Kupkaik Před 7 lety +145

      Can't say I blame him. That's the method that's taught in school, and lets be honest, for the average person it isn't very enticing. I absolutely hated math in school! I never passed a test, infact I had to repeat algebra 3 times! It was stressful. It wasn't interesting, it wasn't fun, it wasn't intriguing. However, now that I've graduated from high school, I've seen the prettier side of math that, if I had learned and saw back then, would have been very interesting and more stimulating to learn! But now we're getting into psychology a bit, and for the average everyday person, if you're failing at things, you lose interest.
      I still do not like the way math is taught in school, because of what you said IS what happens. They don't show us interesting things! but now I'm just getting repetitive.

    • @nightangel7239
      @nightangel7239 Před 7 lety +67

      Ellie The Snow Fairy
      The issue is that the interesting things have a lot of math going into them, so teaching the interesting things off the bat will either be useless (You won't explain the math) or difficult (Hard math).
      Examples include all the popsci channels on youtube. How many channels are there, exactly, like VSauce? Numberphile? Honestly, even Standup Maths to a very small extent, where they teach you really cool ideas, and you get a sense of "Now I know more", but in the end you're still just as bad at math and science as before?
      It's easy to get people interested in black holes, rocketry, quantum physics, and to tell them things like "The sun is like a big nuclear reactor! And it's like nuclear bombs are going off in the center constantly! Computer chips are so small, electrons can jump from one circuit to another by chance because of quantum mechanics!", but at the end of the day they don't understand a thing of how it works. They can't even tell you how fast a ball will roll down a ramp, even if they memorized the analogy for the double-slit experiment.
      All that happens is they feel smart and then they comment "OMG, why doesn't anyone else like this stuff? Is it because I'm smarter than everyone around me?". Then they make idiots of themselves by taking analogies seriously. "If a human doesn't look at a particle, then it doesn't exist! Uncertainty! Schrodinger!".
      To summarize:
      Education is a hell of a bitch to handle. People who are good at it seriously deserve to be more distinguished.

  • @eddiegaltek
    @eddiegaltek Před 8 lety +185

    You have to go down to -1/1583 to get as good an approximation as 22/7.

  • @timyang2996
    @timyang2996 Před 4 lety +796

    perfect for my pi memorization contest i could just calculate it on the spot

    • @patrickboner
      @patrickboner Před 4 lety +13

      @Viktor Magnusson you would be surprised some people can especially if you look at your memory as a piece of paper and pen

    • @Sora_Halomon
      @Sora_Halomon Před 4 lety +19

      all you need is the list of all known prime numbers

    • @patrickboner
      @patrickboner Před 4 lety +3

      @@Sora_Halomon please explain

    • @efdbjon2114
      @efdbjon2114 Před 3 lety

      @@Sora_Halomon just use the nth term for the prime numbers

    • @JohnDoe-eu2vv
      @JohnDoe-eu2vv Před 3 lety

      Might be easier to use a faster series

  • @ashaydwivedi420
    @ashaydwivedi420 Před 6 lety +549

    How fascinating, the calculation of pi starts at 3:14

  • @TazPessle
    @TazPessle Před 7 lety +882

    When i was 6 i thought they made bigger and bigger circles and measured with better and better rulers to find the digits of Pi. XD

    • @htmlguy88
      @htmlguy88 Před 7 lety +51

      you can use trig functions to estimate it using polygons with more and more sides it's been done up to millions of sides in the past I think.

    • @Bjowolf2
      @Bjowolf2 Před 7 lety +46

      Already the Greek mathematician Archimedes did this up to an amazing 96 sided inner and outer
      polygon.
      en.wikipedia.org/wiki/Archimedes#Mathematics

    • @Bjowolf2
      @Bjowolf2 Před 7 lety +8

      But then you need to know the trig functions to a high accuracy ;-)

    • @ffggddss
      @ffggddss Před 7 lety +12

      + Bjowolf2
      All you need to know about the trig functions to use Archimedes' method is:
      sin30º = ½
      tan30º = 1/√3
      and the half-angle formulas for both sin and tan.
      Which in turn, means that you have to know how to extract square roots.

    • @Bjowolf2
      @Bjowolf2 Před 7 lety +2

      ffggddss Yes, I know, but did the Greeks know that and how to do that?

  • @karlmuster263
    @karlmuster263 Před 8 lety +1576

    My favorite representation is 355/113 = 3.1415929203... It's easy to remember. You start with the first three odd numbers: 135. You double them up: 113355. You split it in the middle: 113/355. Then you take the inverse: 355/113. And there you have it, pi correct to 7 digits.

    • @SamFisk
      @SamFisk Před 8 lety +72

      Having seen the final result I think I agree that this is better. Another commenter has pointed out that this is accurate to a 1/3748629th; good enough and much easier to calculate.

    • @derrickbonsell
      @derrickbonsell Před 7 lety +16

      +Sam Fisk It'd be easier to just remember the digits.

    • @SamFisk
      @SamFisk Před 7 lety +2

      Each to his own. I'd just use Google...

    • @77gravity
      @77gravity Před 7 lety +5

      The purpose of an approximation like 553/113 is for use in longhand calculations.

    • @karlmuster263
      @karlmuster263 Před 7 lety +1

      77gravity And sometimes physicists use fractions, like when using the fine-structure constant, a~1/137.

  • @braylordian5541
    @braylordian5541 Před 6 lety +1098

    The best way to find pi is the equation:

    • @goji_crafter
      @goji_crafter Před 5 lety +150

      Here, ill solve it for you:
      Let pi = x
      1pi=x
      Divide both sides by pi
      1=x/pi
      Now we can find the real value.
      So if I hit backspace three times on the last step, we find that:
      1=x, so pi=1

    • @Aspiracy
      @Aspiracy Před 4 lety +6

      xX GojiCrafter Xx lmao

    • @patrickboner
      @patrickboner Před 4 lety +2

      @@goji_crafter forgot the sign change

    • @kerbalpanda3592
      @kerbalpanda3592 Před 4 lety +2

      @@goji_crafter underrated comment
      ik this was a year ago

    • @phatkin
      @phatkin Před 3 lety +12

      that's not an equation, that's an expression. You can tell because an equation typically has an equal sign.

  • @kaazmodan
    @kaazmodan Před 6 lety +112

    I really love the idea of a student randomly walking in on this happening, seeing Matt talk to himself and writing on the chalkboard, and then just saying "He's just having one of his "special" days", then walking out without saying anything.

    • @JiMwB
      @JiMwB Před 3 lety +6

      One of those days where you
      1st try to find π
      2nd start turning into a Smurf
      3rd murder a Smurf
      4th fail at finding π

  • @servalerror
    @servalerror Před 8 lety +506

    Uploaded on March 13, not the 14th...classic Parker Square.

    • @wallonice
      @wallonice Před 5 lety +4

      Its pi, classic parker circle

    • @Jivvi
      @Jivvi Před 4 lety +6

      No, it was 3/14/16
      Correct to 4 decimal places.

    • @OpRaven-62
      @OpRaven-62 Před 4 lety

      @@Jivvi technically it's 3.14159... but I guess yeah, 3.1416

    • @david-li3mn
      @david-li3mn Před 4 lety

      @@OpRaven-62correct to 4

    • @DrKaii
      @DrKaii Před 3 lety

      @niraj panakhaniya someone ruined it niraj, we must find them

  • @chinareds54
    @chinareds54 Před 8 lety +158

    I'm 37 years old, and this is the first time I've ever seen long division done on one line rather than taking up a whole damn page. Wow.

    • @Jiggerjaw
      @Jiggerjaw Před 8 lety +15

      +chinareds54 I am 25; when I was in grade school, this method was taught under the name "short division".

    • @dolantremp
      @dolantremp Před 8 lety +10

      +chinareds54 lol yeah this way is much more convenient i have no idea why they dont teach it instead

    • @SomeRandomFellow
      @SomeRandomFellow Před 8 lety

      +Brenden Patch that explains why there's a long division and not a short division

    • @rhythmic700
      @rhythmic700 Před 7 lety

      that is called short division fyi

    • @squidbait1396
      @squidbait1396 Před 7 lety

      wait what? this is the only way i've ever seen long division done. what is this other method?

  • @kurumi394
    @kurumi394 Před 4 lety +462

    Archimedes: approximates pi to the second digit with a 96 sided polygon
    *Zu Chongzhi: laughs in 24576 sided polygon and 7th digit of pi*

    • @peorakef
      @peorakef Před 3 lety +8

      you're aware that was 800 years afterwards?

    • @kurumi394
      @kurumi394 Před 3 lety +58

      @@peorakef Yes. That doesn't mean it's less of an extraordinary feat though.

    • @peorakef
      @peorakef Před 3 lety +5

      @@kurumi394 Yes. That doesn't mean you have a point.

    • @j.moonstorm3158
      @j.moonstorm3158 Před 3 lety +10

      Archimedes also invented calculus in his lost magnum opus "The Method" a feat not replicated for a few thousand years after a number of mathematic advances were made that archimedes didn't have access to so...he's arguably the most brilliant mathematician to ever live

    • @eleSDSU
      @eleSDSU Před 3 lety +5

      @@j.moonstorm3158 I'll disagree in one word, Euclid.

  • @bungalo50
    @bungalo50 Před 2 lety +19

    This really highlights how amazingly precise 22/7 actually is

    • @carultch
      @carultch Před rokem +1

      This also highlights how well you can do just by measuring a circle with a piece of string.

  • @theCodyReeder
    @theCodyReeder Před 8 lety +1960

    You could multiply it by 2 and get tau. :)

    • @Talt9999
      @Talt9999 Před 8 lety +122

      I love finding one of my favorite youtubers commenting on loads of the science/maths youtube videos i watch :)

    • @standupmaths
      @standupmaths  Před 8 lety +370

      +Cody'sLab But I was trying to calculate the circle constant… :]

    • @Kylanto
      @Kylanto Před 8 lety +34

      +standupmaths Roasted!

    • @newgoredan303
      @newgoredan303 Před 8 lety +4

      +Cody'sLab Holy crap, Cody!

    • @hughmongusfungusamongus2439
      @hughmongusfungusamongus2439 Před 8 lety +7

      +standupmaths Nice one

  • @EpicUltraKingSmizzy
    @EpicUltraKingSmizzy Před 8 lety +341

    was this like a secret 'learning how to divide' video? lol

    • @Regular-Sized
      @Regular-Sized Před 8 lety

      +EpicUltraKingSmizzy my thoughts exactly.

    • @MegaMGstudios
      @MegaMGstudios Před 7 lety +14

      this is actually where i learned to divide in my head, they didnt teach me that on school, they legit said "just divide"

    • @Berniebud
      @Berniebud Před 6 lety +14

      I learned how to divide long ago but forgot, now I know again.

    • @Metalhammer1993
      @Metalhammer1993 Před 6 lety +2

      same here i entirely forgot to divide by hand due to calculators^^

    • @azestical6566
      @azestical6566 Před 6 lety

      MegaMGstudios that is really sad ._.

  • @alejrandom6592
    @alejrandom6592 Před 3 lety +22

    2:34 POV: you enter an empty classroom and there's a man randomly shouting "chalkboard"

  • @TomStorey96
    @TomStorey96 Před 4 lety +35

    I had completely forgotten how to divide numbers like this.

  • @Toost914
    @Toost914 Před 8 lety +474

    I wonder how many pieces of chalk went into making this video...

  • @kevinocta9716
    @kevinocta9716 Před 8 lety +61

    I have no idea why, but I could watch this man do basic math for hours. Honestly... it's odd.

    • @Jbenneballe
      @Jbenneballe Před 8 lety +1

      +Kevin Octacok glad to hear i'm not alone with that feeling :)

    • @Summy_99
      @Summy_99 Před 8 lety +3

      yeah I could literally watch him do the whole thing with no cuts

    • @kyleserrecchia7234
      @kyleserrecchia7234 Před 8 lety

      +Kevin Octacok It's like a meditation. It's simple, but it's so beautiful in its perfection.

    • @Reivivus
      @Reivivus Před 8 lety

      +Kevin Octacok, most of what he is talking about I already know so it's not like I'm being educated. Where is the original research?

    • @kevinocta9716
      @kevinocta9716 Před 8 lety

      Reivivus
      The original research is that man's beautiful face and charming wit.

  • @topdog8035
    @topdog8035 Před 7 lety +420

    my favourite part was 3:14

    • @cyberfalcon2872
      @cyberfalcon2872 Před 6 lety +66

      Actually, thats the part that the video really starts. I wonder if that was a coincidence

    • @fanq_
      @fanq_ Před 6 lety +13

      Thiago Morais probably not

    • @Boonda-p
      @Boonda-p Před 6 lety +11

      no way. on a separate note i love when people spell favorite with a u

    • @prakharsingh9089
      @prakharsingh9089 Před 5 lety +1

      lol

    • @GerassimosOfficial
      @GerassimosOfficial Před 5 lety +1

      @@prakharsingh9089 xd

  • @Mdibah
    @Mdibah Před 7 lety +17

    Mistake #1 (fixed during montage at 13:08): incorrect number of decimal places written for 1/17
    Mistake #2 (@ 12:00): The difference of the decimal expansions given for 1 and 1/3 should be 0.66...667. This throws off the 20th decimal place for the rest (meh).
    Mistake #3 (visible @13:03): After adding the decimal for 1/13, the partial sum should be 0.820 934 620 934 620 934 62 (vicinity of 7th decimal place on is wrong). This throws off the rest of the calculation.
    The ending tally should be 0.760 459 904 732 350 552 78, which gives 3.041 839 618 929 402 211 12 after multiplying by 4. Again, very close---just issues around the 7th and 8th decimal places.
    Mad props for carrying out this masochism by hand; I needed to break out a calculator to track down the arithmetic error.

  • @12tone
    @12tone Před 8 lety +33

    I know this probably didn't affect the outcome very much, but your value for 1-1/3 should've ended in a 7, not a 6, right? Like, if you're doing it by approximating 2/3 then it needs to end there because the next digit is a 6 so it should round up, and if you're doing it by subtracting a truncated series of threes from a truncated series of 0s, I'm fairly certain that 10-3=7.

  • @codebroker_
    @codebroker_ Před 8 lety +256

    Well if nothing else at least I learned the British way to divide

    • @inserttheemailyouusehere1480
      @inserttheemailyouusehere1480 Před 7 lety +33

      Cole Vohs British way? I thought it was common knowledge

    • @diamonddave2622
      @diamonddave2622 Před 6 lety +12

      he's Australian

    • @micrapop_6390
      @micrapop_6390 Před 6 lety +1

      The way to multiply too !

    • @silkwesir1444
      @silkwesir1444 Před 6 lety +7

      I don't like it, because it looks a lot like a square root symbol.
      I tend to dislike any notation which could be confused for being something else...

    • @franciscodanconia45
      @franciscodanconia45 Před 6 lety +14

      That’s the way everyone did it before pocket calculators were invented! “Never throw away your last pencil.”-me

  • @DhananjayDhole-DD
    @DhananjayDhole-DD Před 6 lety +26

    I got curious by how slowly the series converges to PI/4 and started running calculations. I was observing the absolute error for PI at each step and found a bit of interesting pattern. Below are the first 11 values of (2n + 1) at which the absolute error falls further by a factor of 10.
    63, 637, 6367, 63661, 636619, 6366197, 63660819, 636485221, 6334383829, 61037411473
    Found it fascinating
    1) How the 63....... pattern holds from for the first few elements
    2) How 63 is about 20xPI (62.832), thus 637 is ~200xPI and so on. It's a convenient factor of 10 if we use Tau over PI, but lets not go there :-). I prefer PI as anyway

  • @lollycopter
    @lollycopter Před 2 lety +31

    14:17 The full answer of Pi is revealed right here.

  • @jackeown
    @jackeown Před 7 lety +111

    Python one-liner:
    4*sum([(-1.0)**(k)/(2*k+1) for k in range(0,10,1)])

    • @beckles103
      @beckles103 Před 4 lety +11

      John McKeown step is 1 by default

    • @RoyBrush
      @RoyBrush Před 4 lety +7

      In case people want to run this in their browser in place, here is a roughly equivalent one-liner in javascript:
      ((t)=> 4*(new Array(t)).fill(0).map((_,i)=>Math.pow(-1,i)/(2*i+1)).reduce((a, v)=> a+v))(10)
      You might also want to explicitly console.log the result of the above expression and/or change the precision like so:
      console.log(((t)=> 4*(new Array(t)).fill(0).map((_,i)=>Math.pow(-1,i)/(2*i+1)).reduce((a, v)=> a+v))(10000000))

    • @jackeown
      @jackeown Před 4 lety +1

      @@beckles103 good point.

    • @x_star6100
      @x_star6100 Před 4 lety +6

      this is wrong
      i got 3.0418396189294032
      xD

    • @jackeown
      @jackeown Před 4 lety +7

      @@x_star6100 It's an approximation. Replace the 10 with a much higher number and you will get a better approximation. try 10000 or higher and you'll see it gets a little better. Convergence is very slow though.

  • @terryendicott2939
    @terryendicott2939 Před 8 lety +106

    At 13:14 you said, "The trouble with using red chalk after blue chalk is now it looks like I murdered a smurf." in a tone that sounded like you thought that murdering a smurf might be a bad thing.

  • @jraqn
    @jraqn Před 4 lety +29

    I want this guy as my math teacher he's cool

  • @MichaelWilliams-ow9ue
    @MichaelWilliams-ow9ue Před 5 lety +5

    I’m genuinely inspired and impressed an an adult professional mathematician who has spent years learning advanced mathematics can still enjoy this so much. I am a musician and this would be the equivalent of me being excited by playing a scale or Mary had a little lamb, which just doesn’t happen.

  • @Dixavd
    @Dixavd Před 8 lety +46

    14:08 - as we all know, four threes are twenty-eight.

    • @kdmq
      @kdmq Před 8 lety

      +Dixavd That was just a speech error. He was pointing to a seven as he said three and the product of 28 is correct.

    • @Dixavd
      @Dixavd Před 8 lety

      kdmq
      Oh I know, I just thought it was funny.

    • @birthsonbluebell3654
      @birthsonbluebell3654 Před 6 lety

      4+[3×(4+4)] is 28.

  • @criotene
    @criotene Před 8 lety +56

    i fell asleep on a vans gaming video and woke up to this

  • @brandonmonroe9822
    @brandonmonroe9822 Před 2 lety +1

    One of my favorite videos you've ever made. I've learned SO MUCH from this video. I could never thank you enough.

  • @mgsquared5204
    @mgsquared5204 Před 7 lety +253

    He wrote 1.0000000... Like 1•0000000..

    • @mgsquared5204
      @mgsquared5204 Před 7 lety +16

      GamerGeek like multiplication.

    • @ffaiq
      @ffaiq Před 7 lety +5

      UK thing

    • @jaythatch7295
      @jaythatch7295 Před 6 lety +6

      Well that's how we do it in grade school, but the dot is used to avoid confusion with x as a variable.

    • @matthewbertrand4139
      @matthewbertrand4139 Před 6 lety +14

      CubeMania We do any of three things. We could write that as:
      6 × 2
      6 * 2
      6 • 2
      My preferred method is the dot. It's quickest to write and avoids confusions with any variables named x.

    • @markdallen4018
      @markdallen4018 Před 6 lety +14

      The letter x and multiplication symbol are very different in UK mathematics, so it's easy to distinguish between them. The x is curly, and the multiplication symbol is too straight lines crossing.

  • @alexchulzhanov
    @alexchulzhanov Před 8 lety +307

    I'm sorry but you draw your decimal points way too high and they look like dot products or something XD

    • @standupmaths
      @standupmaths  Před 8 lety +197

      I'm saving money with cheap low-density decimal points. But they do tend to drift off.

    • @alexchulzhanov
      @alexchulzhanov Před 8 lety +9

      +standupmaths Haha that made it better XD

    • @lapk78
      @lapk78 Před 8 lety +8

      +standupmaths That's one of the best retorts I've ever seen in a comment thread. Beautiful. But why not splurge a bit for PiDay? Get the good stuff.

    • @Correctrix
      @Correctrix Před 8 lety +5

      +byalexandr You draw your decimal points way too low and they look like full stops.

    • @__nog642
      @__nog642 Před 8 lety +5

      Correctrix periods and decimal points are the same character
      ..

  • @anarcho.pacifist
    @anarcho.pacifist Před 8 lety +22

    The 8th digit after the decimal point should be 0, instead of 9, at 13:12
    The correct results are: 0.76045990473235055278398931649706 and 3.04183961892940221113595726598823

  • @georgew.9663
    @georgew.9663 Před 6 lety

    Holy crap that transition to the chalkboard was seriously amazing, I've never seen a transition like that anywhere near as good as you did that, Jesus Christ.

  • @shadowpod13
    @shadowpod13 Před 6 lety

    I like that you're calculating pi without using any Sin stuffs. Makes it easier to follow. Also, at the same time you are explaining what happens when I put a fraction into a calculator. Real cool.

  • @leocorn58
    @leocorn58 Před 7 lety +169

    "Oh that's neat. I wonder how that works."
    "Woah cool, he knows his stuff."
    "Okay, can't wait to see how he knows this."
    "HE'S A WITCH!!!"

    • @tonksdude
      @tonksdude Před 5 lety +6

      What do you do with witches?

    • @jackmack1061
      @jackmack1061 Před 5 lety +4

      burn them?

    • @tonksdude
      @tonksdude Před 5 lety +2

      @@jackmack1061 gooooooooooooooooooooooooooood

    • @tonksdude
      @tonksdude Před 5 lety +9

      @@jackmack1061 and what do you burn aside from witches?

    • @jackmack1061
      @jackmack1061 Před 5 lety

      lol, that movie terrified me as a child. Nightmares...

  • @TommiHimberg
    @TommiHimberg Před 8 lety +37

    Damn, we are 10 days late in celebrating pie day!

  • @bryankurniawan5397
    @bryankurniawan5397 Před 5 lety

    OMG THIS GUY IS SO GOOD AT MAKING ME FALL ASLEEP IM NOT BORED BUT HIS VOICE MAKES ME SOO SLEEPY IDK WHY BEST VIDEO SO FAR.

  • @JosiahDouglas
    @JosiahDouglas Před 5 lety

    This is the most ridiculously wonderful thing I've ever seen. Thank you CZcams for suggesting this.

  • @asp-uwu
    @asp-uwu Před 8 lety +12

    Another way you can find π:
    π=3+(4/[2*3*4])-(4/[4*5*6])+(4/[6*7*8])
    I wrote a program to calculate π using both the method you did in this video, and the one above, and it turns out the one above gets much closer with many fewer iterations. Great video sir!

    • @chainezo
      @chainezo Před 8 lety +1

      +Eric Pratt but prime numbers tho

  • @jordansmith2520
    @jordansmith2520 Před 8 lety +61

    3:14 It's amazing... He starts calculating pi at pi time value.

  • @andrewmartin3671
    @andrewmartin3671 Před 2 lety +5

    I'm here for Parker Pi references.

  • @liliacfury
    @liliacfury Před 5 lety

    I love the way you divide, the way I was taught takes up so much space. Nice to know.

  • @NikolajLepka
    @NikolajLepka Před 8 lety +45

    why do I suddenly understand how to do division by hand after watching this?

    • @cupcakearmy
      @cupcakearmy Před 8 lety

      Me too 😊

    • @S4R1N
      @S4R1N Před 8 lety +2

      +Nikolaj Lepka Yup, I'm watching this while procrastinating/finding motivation to study for a math exam (albeit a very basic one).
      I can now to division by hand magnitudes easier than what I was originally taught.

    • @NikolajLepka
      @NikolajLepka Před 8 lety +1

      S4R1N
      We were taught long division at school, and it was so cumbersome and confusing I never really bothered to learn it.
      Now, I'm a programmer, so I deal with integer division and modulo operations all the time, so short division just seems so much more natural, because all it deals with is remainders

  • @kocajj
    @kocajj Před 7 lety +5

    I love how excited you were doing the long division. It actually made me remember my days in 3rd grade when I was learning more complex long division and thinking of how your enthusiasm would have made the process much more enjoyable; more of a game, rather than a chore. I will make sure to pass that on to my son when he gets older.

  • @MattMcIrvin
    @MattMcIrvin Před 6 lety +2

    The French translator in the captions captured Matt Parker's speaking style quite well.

  • @poipoi
    @poipoi Před 2 lety +10

    here after finding out this is *actually* the value of pi

  • @legofan431
    @legofan431 Před 7 lety +58

    I love how happy he gets over dividing 1/17 in his head :D

  • @sasukesuite1
    @sasukesuite1 Před 8 lety +189

    Sorry, but your first calculation is wrong. 1/1 = 0.999999999....

    • @jeromesnail
      @jeromesnail Před 8 lety +15

      Actually it is. 0,9999999999999... = 1

    • @epicfailtackular
      @epicfailtackular Před 8 lety +12

      it was a joke, pal

    • @vernement4752
      @vernement4752 Před 8 lety

      +jeromesnail Difference?

    • @Pattonator14
      @Pattonator14 Před 8 lety +18

      Except that he's rounding up after 20 digits, so 0.999999... would be rounded up to 1.000000... etc anyway

    • @jeromesnail
      @jeromesnail Před 8 lety

      +verne ment no difference, I just misunderstood the comment. My bad!

  • @Sacorian
    @Sacorian Před 7 lety

    I finally understand how the digits of Pi can be seemingly all over the place. Thank you Matt Parker.

  • @thebenevolentsun6575
    @thebenevolentsun6575 Před 6 lety

    I've been waiting for this channel to exist

  • @LarlemMagic
    @LarlemMagic Před 8 lety +154

    A real parker square that was. :)

  • @patrickwienhoft7987
    @patrickwienhoft7987 Před 8 lety +28

    The series up to n = 19 is actually 3.041839 (here you get wrong) 61893... Not sure where the error is tho.
    edit: got it! (assuming its the only mistake). 13:03
    1-1/3+1/5-1/7+1/9-1/11+1/13 is 0.82093462093..., not 0.82093471093...
    edit2: yes, with that result I get your "pi" :)

  • @jdat
    @jdat Před 6 lety

    I seriously learned multiple tricks from the video! Thanks for teaching me some easy techniques! I'm currently taking algebra 1 in 8th grade (US) so I'm sure these will be used a LOT!

  • @DanielRBW
    @DanielRBW Před 6 lety +4

    I've discovered (through excessive use of excel), that the number of iterations is equal to the degree of accuracy. So at the 10000th iteration, the value is equal to pi to 5 s.f. At 1 million iterations, the value is equal to 3.141592 (rounded), which means it is accurate to 1 part in every million. Either way, I thought that was pretty interesting, although it maybe should have been more obvious, looking at it in hindsight.

  • @putinstea
    @putinstea Před 7 lety +358

    3:22 Why would you draw the "point" there? It looks like a multiplication symbol.

    • @SJN3000
      @SJN3000 Před 7 lety +36

      Iorveth AFAIK this is a thing in the UK

    • @entropyzero5588
      @entropyzero5588 Před 7 lety +33

      I've also seen people on this channel drawing the multiplication symbol where the rest of us would place the decimal point and was quite confused - apparently this is normal somewhere?

    • @Pteromandias
      @Pteromandias Před 6 lety +31

      It's not normal anywhere. Nothing is normal in Brexitannia.

    • @danjbundrick
      @danjbundrick Před 6 lety +4

      Yeah, it's their thing. With a bit of discernment, you can translate it to the American way. Cheers.

    • @sp00kiestchannelevah76
      @sp00kiestchannelevah76 Před 6 lety +13

      Sorry, who uses a point as a multiplication sign? X has always been the sign that I've known... Or * for computers

  • @modakshantanu
    @modakshantanu Před 8 lety +40

    This video is 1119 second long.
    If you make a circle with diameter 1119m, it's circumference is 3515 m.
    3515/1119 =3.14.
    Nice Easter egg.

    • @ju-inhum7896
      @ju-inhum7896 Před 8 lety +12

      Sorry to burst your bubble, but that is no Easter Egg... Diameter is (2 * radius) and circumference is (2 * pi * radius). Therefore, by dividing circumference by diameter, regardless of the value, will always return pi.

    • @sebamc4
      @sebamc4 Před 8 lety +1

      +Shantanu Modak NICE! .... ;)

    • @ju-inhum7896
      @ju-inhum7896 Před 8 lety +2

      Also, you used the wrong "its/it's". Although the apostrophe is usually used for the possessive form, in this case, it is used to contract "it" and "is" into a single word. Additionally, I'm pretending to be smart by being fancy.

    • @ju-inhum7896
      @ju-inhum7896 Před 8 lety

      +sebamc4 Listen, it's not an Easter Egg, ok? Do it with any other number and you'll see.

    • @sebamc4
      @sebamc4 Před 8 lety +5

      Ju-In Hum yes, i had math in high school. I was playin the joke along... thats why i put the ";)"

  • @peterflom6878
    @peterflom6878 Před 4 lety

    His excitement and sense of wonder are beautiful

  • @popcet224
    @popcet224 Před 6 lety

    Matt is so awesome i'd watch him divide and substract all day and not sleep in class

  • @timothy9958
    @timothy9958 Před 8 lety +19

    Really liking the consistent uploads. you're doing a good job man!

  • @nmanrman911
    @nmanrman911 Před 8 lety +110

    You could call this attempt a "Parker square" of Pi
    :P

  • @Zachdancer1
    @Zachdancer1 Před 3 lety

    I’m excited to see what he does this year!

  • @leighhurley9410
    @leighhurley9410 Před 5 lety

    The editing absolutely makes this video XD

  • @circular17
    @circular17 Před 8 lety +52

    The correct result would be 3.0418396189294022111359572659882 so Matt got the first 7 digits right and then, well, not correct. But anyway, the correct result is still way off Pi!!

    • @SGAMaddin
      @SGAMaddin Před 8 lety +6

      The result given by you is the one i got too; I think he made a typo when adding the numbers; his result for pi/4 is correct apart from the eighth digit where it should read 0 instead of 9; pi/4 = 0.7604599 0 47323505528. But still very impressive doing it by hand that well. I did it with Mathematica.

    • @klobiforpresident2254
      @klobiforpresident2254 Před 8 lety

      Don't forget that he used only ten fractions out of a literal infinite pool, ...

    • @SPACKlick
      @SPACKlick Před 7 lety

      He made the mistake at 1/13

    • @ashortguy24
      @ashortguy24 Před 3 lety

      @@SGAMaddin It would be incorrect he didn't use all the numbers, and adding rational numbers give a rational result, unless added infinitely

  • @warpcore0541
    @warpcore0541 Před 8 lety +14

    14:09 Four threes are twenty eight!
    At least that was a seven.

    • @utl94
      @utl94 Před 8 lety +2

      +warpcore05 Wow! He was lucky that was a seven...

  • @thermitebanana
    @thermitebanana Před 6 lety

    I love the working out. Just an awesome example of getting results through hard work and persistence

  • @mrchel2525
    @mrchel2525 Před 6 lety

    I was looking for something like this really long time. Thank you for this video! :)

  • @sezylrin4138
    @sezylrin4138 Před 8 lety +16

    no smurfs were hurt in the making of this video :P

  • @lasagnahog7695
    @lasagnahog7695 Před 8 lety +35

    "Doing a Third the Long Way" should be your biography's title.

    • @lasagnahog7695
      @lasagnahog7695 Před 8 lety +2

      Never mind "Smurf Fingers" would be better.

    • @standupmaths
      @standupmaths  Před 8 lety +6

      "One man's battle with recurring digits."

    • @marsamet128
      @marsamet128 Před 8 lety +1

      +Eric Loesch Are you sure? I think "Smurf Murderer" is a lot better

    • @IrizarryBrandon
      @IrizarryBrandon Před 8 lety

      +dopplegänger_01 Yes, I was initially more fascinated by that han the actual discussion of pi itself. I guess that shows the real level of my mathematical understanding! Oh well, you have to learn to crawl before you can learn to walk, as they say.

    • @IrizarryBrandon
      @IrizarryBrandon Před 8 lety

      Yes, same here, actually (sorry if my comments mislead). It seems like a pretty practical method. Who knows? I may use it in the future.

  • @kone6689
    @kone6689 Před 3 lety +4

    Why does he look like Doug DeMuros brother?

  • @0x13a9
    @0x13a9 Před 5 lety +1

    This guy is awesome, I wish he was my teacher. Thanks you for the content.

  • @TheChondriac
    @TheChondriac Před 8 lety +24

    Nice Rebecca Black reference in the first 5 seconds.

    • @glialcell6455
      @glialcell6455 Před 8 lety +1

      +Josh Hansen lol even he was cringing at it.

  • @axiezimmah
    @axiezimmah Před 8 lety +102

    couldn't you theoretically use this in reverse to calculate prime numbers?

    • @michaelbauers8800
      @michaelbauers8800 Před 8 lety +36

      My intuition is that you would not be able to decompose PI back to primes like that. Seems intractable.

    • @klobiforpresident2254
      @klobiforpresident2254 Před 8 lety +17

      You *could* do this but it is ... impractical.

    • @htmlguy88
      @htmlguy88 Před 7 lety +32

      my guess is no simply because you need to know if they are 1 or 3 mod 4 to know if they were added or subtracted.

    • @joaopedroholanda4167
      @joaopedroholanda4167 Před 5 lety +3

      Hm. I don't see how. In order to calculate a single term of the series you would need to know the partial sums... which would require knowing the terms to calculate. Unless there's a closed formula for the partial sums, which I doubt, this doesn't seem feasible.

  • @21.nivruttt14
    @21.nivruttt14 Před 2 lety +2

    did you know that pi day in the year 2014 was a Friday

  • @catamountcubing4851
    @catamountcubing4851 Před 4 lety +8

    i love how he said, "and we carry the nothing"

  • @grahamrich9956
    @grahamrich9956 Před 8 lety +16

    You were inconsistent with your little jump on the first subtraction. Earlier on, you said that you would round up 6's, but then you failed to do so for 2/3. Of course, that's what the subtraction would have given you, but still.

    • @standupmaths
      @standupmaths  Před 8 lety +22

      Well spotted! I should not have been inconsistent; I reckless added the rounding policy partway through the calculation.

    • @ju-inhum7896
      @ju-inhum7896 Před 8 lety +12

      +standupmaths You also recklessly replied to that comment and forgot to transform "reckless" into an adverb. But hey, this isn't Stand Up English!

    • @roshantruax9134
      @roshantruax9134 Před 7 lety +2

      I love how he didn't even respond to your comment.

  • @DaveScottAggie
    @DaveScottAggie Před 8 lety +4

    Woah, I saw the 3.04 and thought "wait". Then I recalled that this is a slow series. I did not realize how slow though till I decided to try it. Between the fractions 1/173 and 1/175 it starts oscillating between 3.13 and 3.15, but it is quite awhile (around 1/579) before the digits actually round to 3.14, but it is still oscillating between 3.14..... (rounding down) and 3.13..... (rounding up).

    • @shubzilla755
      @shubzilla755 Před 8 lety

      +David Scott A properly weighted average of the last three terms gives a result of 3.14091... with only 10 terms (-1/19)

  • @liamgeisler1204
    @liamgeisler1204 Před 7 lety

    It's fun to watch someone so passionate about mathematics.

  • @toasterwafflz5694
    @toasterwafflz5694 Před 5 lety

    For some reason watching you divide fractions made me happy

  • @jamief415
    @jamief415 Před 8 lety +22

    Can you do a video on a proof of why the (1 +/- 1/(prime)) series equals 2/pi?

    • @felipea.barretto7503
      @felipea.barretto7503 Před 8 lety

      +Jamie F Do a matt parker explains out of this!

    • @decdedceeded
      @decdedceeded Před 8 lety +1

      It's actually just a disguised version of the odd reciprocals, you just factorise and use geometric series (essentially)

  • @TristanBomber
    @TristanBomber Před 8 lety +16

    Matt! What's up with those odd decimals? They look like multiplication!

  • @calvinnel3954
    @calvinnel3954 Před 4 lety

    just have to say i love your delivery

  • @anitas.8427
    @anitas.8427 Před 6 lety

    Great video, was never in my life so close to understand dividing :D

  • @autodidactusplaysjrpgs7614
    @autodidactusplaysjrpgs7614 Před 8 lety +25

    1/19 the struggle is real lol

  • @WolfOfLegend
    @WolfOfLegend Před 8 lety +35

    Wouldn't the 2/3 be 0.66666..67 due to rounding?

    • @Filmsuper95
      @Filmsuper95 Před 8 lety +2

      +DrPengin 1,000,000 Media 0.000...04 because he multiplies with 4

    • @kisaragiayami
      @kisaragiayami Před 8 lety +1

      +DrPengin 1,000,000 Media That is 0

    • @kaytontruong2739
      @kaytontruong2739 Před 8 lety +1

      +WolfOfLegend No, it would not be due to rounding because there *is no rounding.*
      It's just like how 0.999... = 1 without "rounding" of any sort.

    • @ffggddss
      @ffggddss Před 8 lety

      +Ginger Bread
      Yes, it IS rounding; round infinitely many sixes to 19 sixes and a seven, which is twice as close to true as rounding it to 20 sixes.
      And, yes, an infinite string of 9's will equal 1; but a finite string of 9's will not.

    • @NoriMori1992
      @NoriMori1992 Před 8 lety

      +ffggddss But Matt was obviously truncating rather than rounding.

  • @d4m4s74
    @d4m4s74 Před 7 lety

    I totally forgot how long or short division worked after years and years of not using it. Thanks for the refresh.

  • @igor-math-br
    @igor-math-br Před 7 lety

    I love math and among all the videos I've seen in CZcams YOURS IS THE MOST INCREDIBLE OF ALL. Thank you for almost going mad with all these calculations. I surely going to subscribe to your channel e watch all videos about π.

  • @dotMarauder
    @dotMarauder Před 8 lety +8

    14:28, "I should tell someone."
    I'm dying.

  • @DanDart
    @DanDart Před 7 lety +50

    "Four threes are twenty eight"
    You have been broken xD

    • @oz_jones
      @oz_jones Před 4 lety +4

      Dan Dart parker multiplication

    • @Jivvi
      @Jivvi Před 4 lety +1

      "Six times nine is forty-two."

  • @aiseop31415
    @aiseop31415 Před 2 měsíci +4

    To be very frank….you are the reason why i m happy right now

  • @Tuxcz
    @Tuxcz Před 7 lety

    Amazing. Never knew you can get Pi out of prime numbers. Thanks for great video.

  • @srayce1_
    @srayce1_ Před 8 lety +57

    Anyone else think he'd be a fantastic Doctor? As in Doctor Who...not just like a doctor

    • @PickelPinApple
      @PickelPinApple Před 8 lety

      +DraconianDragon hmmmm

    • @notanimposter
      @notanimposter Před 8 lety +2

      +DraconianDragon MATH DOCTOR

    • @osenseijedi
      @osenseijedi Před 8 lety +3

      +DraconianDragon
      In fact he has neither confirmed nor denied that he will be the next doctor. So there is hope!
      Its sort of a Schrodinger box of the Doctor.

    • @SkyrimHod
      @SkyrimHod Před 8 lety

      +mr_os a Schrodinger Tardis?

    • @jakobygames
      @jakobygames Před 7 lety +1

      i was literally just thinking this. something about his speach patterns.

  • @199NickYT
    @199NickYT Před 8 lety +8

    Remind me: March 4, 2018. The REAL Pi day.

    • @TheJmax04
      @TheJmax04 Před 8 lety +1

      +Nicholas Wright (Toothpick Nick) April 3rd...

    • @avisian8063
      @avisian8063 Před 8 lety

      +Josh O'fortune 22nd of July

  • @matt5347
    @matt5347 Před 2 lety +1

    here to find the full answer to pi. thanks matt!

  • @jhonnycastlejr.9424
    @jhonnycastlejr.9424 Před 4 lety

    You do what i have always wanted to do since i was a kid, having fun doing math. I love math, algebra more like it, and would love to be a mathematician one day

  • @ayylmao93_12
    @ayylmao93_12 Před 7 lety +15

    "It's pi day, pi day, gotta get down on pi day"
    Sounds familiar...

  • @olleicua
    @olleicua Před 8 lety +183

    Your video is obviously 10 days late! Pi day should be March 4th

    • @elikubler-ross5997
      @elikubler-ross5997 Před 8 lety +5

      +Sam Auciello sorry, but wouldn't it be March 14th? at say... 15 hours? :)

    • @amarpersaud2950
      @amarpersaud2950 Před 8 lety +28

      +Eli Kübler-Ross Well obviously Π is 3.04

    • @JamieDenAdel
      @JamieDenAdel Před 8 lety +6

      +Eli Kübler-Ross It's a joke from the video.

    • @olleicua
      @olleicua Před 7 lety +9

      What is a chanber and how do I find one to go die in?

    • @MrSpookersMcGeeThe1st
      @MrSpookersMcGeeThe1st Před 7 lety +3

      Dude, does your town not have a local chanber? I feel so bad for you, man. That's my favorite place to die! I do it once a month to relax.
      Yes. I die once a month, intentionally. Apparently.

  • @thomasalary6406
    @thomasalary6406 Před 7 lety

    This video has taught me so much i never knew
    Thank you so much

  • @Lambda_Ovine
    @Lambda_Ovine Před 4 lety

    I always hated arithmetic... but now I finally, after years, learned a way to do basic division that actually shows me the concept of division.