Generating Functions and Counting With Them - An Intro

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  • เผยแพร่เมื่อ 14 ม.ค. 2025

ความคิดเห็น • 56

  • @rubberducky62742
    @rubberducky62742 5 ปีที่แล้ว +32

    Hi Patrick, please dear god make the second video. This video taught me more in 15 minutes than my prof did in about 3 hours :)

  • @rafaeltheraven
    @rafaeltheraven 4 ปีที่แล้ว +17

    Hey Patrick, I know it's been over 3 years since this video, but is there a chance you will still make a second video it would be a lifesaver!

  • @solc88
    @solc88 7 ปีที่แล้ว +15

    In the first example, when you go from 1 apple to 2 apples, the answer should be 11 instead of 7 because you missed a banana (and it doesn't make sense that you'd go from 10 ways in the 1 apple case to 7 ways in the 2 apples case). (1 + x + x^2)(1 + x)^4 = x^6 + 5x^5 + 11x^4 + 14x^3 + 11x^2 + 5x + 1, the coefficient for x^2 is 11.

    • @sayantantalukdar9883
      @sayantantalukdar9883 3 ปีที่แล้ว +1

      i wasted 30m trying to think why it's 7 and not 11 & then saw he forgot the banana

    • @Pepe-bg9eg
      @Pepe-bg9eg 2 ปีที่แล้ว

      Apparently, the teacher eliminated one type of element, keeping the same number of elements, perhaps with the intention of not complicating the algebraic process. Otherwise the result is correct.

  • @briansalkas349
    @briansalkas349 2 ปีที่แล้ว

    dood... this is how you teach this stuff, build an intuition and then define it formally. Thank you for this video

  • @RB3565
    @RB3565 8 ปีที่แล้ว +17

    Merry xmas and a prosperous new year to the most valuable youtuber in the world. Blessings🙋

  • @mahamrashid2018
    @mahamrashid2018 8 ปีที่แล้ว +1

    Patrick thankyou so much for such amazing and useful videos!! Could never thank you enough :) You're a hero

  • @bashirgagigi172
    @bashirgagigi172 8 ปีที่แล้ว

    I always watch your videos so I'd like to take a moment and appreciate your hard work !!
    Thank you !! Keep it up and merry Christmas !

  • @AtaAriser
    @AtaAriser 8 ปีที่แล้ว +3

    Got surprised you made a video about Generating Functions, really expanding your range

  • @AG-xi8mn
    @AG-xi8mn 8 ปีที่แล้ว

    Thank you so much for all your videos!! You helped me get a high grade in algebra! Happy Holidays!!:)

  • @GarlitoMc
    @GarlitoMc 8 ปีที่แล้ว +31

    Where did the banana go in the second part?

  • @makemarshall7041
    @makemarshall7041 8 ปีที่แล้ว +2

    Thank you for your videos Patrick(: they are very helpful and have helped me a lot in math. I watch everyone of your videos just for fun. Math is fun(:
    Also, do you know of any physics or engineering how to videos on TH-cam like your channel provides? Thank you. You help infinitely many people with the great subject of mathematics each and everyday.

    • @patrickjmt
      @patrickjmt  8 ปีที่แล้ว +2

      i know there are quite a few of each out there, but i don't have anyone to personally recommend!

  • @vanguard7674
    @vanguard7674 8 ปีที่แล้ว +3

    I love it. Combinatorics was my hardest subject in undergrad.
    If you could please answer this question I'd greatly appreciate it: what is the difference between ordinary generating functions and exponential generating functions?

  • @manavnaik1607
    @manavnaik1607 3 ปีที่แล้ว +1

    Thank you for this life saver

  • @landonazbill122
    @landonazbill122 8 ปีที่แล้ว +3

    My favorite generating function is for the partition of integers. Would be neat if you could do a video on the basic proof where you do the foiling. Anyway, take care Patrick!

  • @zcarla3
    @zcarla3 5 ปีที่แล้ว

    Thank you sooo much!!! Very useful to know how and why these are important in terms of counting.

  • @ShashankKomuroju
    @ShashankKomuroju 7 ปีที่แล้ว +6

    Thanks for the video. You said this is an intro, is there a second part for it ?

  • @priyankavnandwani7779
    @priyankavnandwani7779 6 ปีที่แล้ว

    Beautiful and elegant...Thank you so much!

    • @patrickjmt
      @patrickjmt  6 ปีที่แล้ว

      yes i am! thank you for noticing!

  • @SamVidovich
    @SamVidovich 8 ปีที่แล้ว

    Very great video. More like this!

  • @NotABigTruckCycling
    @NotABigTruckCycling 7 ปีที่แล้ว

    I just started learning this topic today for the first time. I could follow the examples in the book but I still felt like I didn't exactly 'believe' what they were doing worked. I appreciate you making the tables to show that you get the same result. It really helped prove to me that the concept makes sense.
    There is just one thing though - I am still not really clear on why anyone would have thought to do this in the first place or why exactly it works. Does it have anything to do with orthogonality? (that's just a wild guess)
    Also, why 'generating' functions? I don't understand why the term 'generating' makes sense in this context.

  • @howmathematicianscreatemat9226
    @howmathematicianscreatemat9226 6 ปีที่แล้ว +1

    As only two people have pointed out: bananas are missing, so we would have to consider the coefficient of x^2 in the polynomial (1+x+x^2)*(1+x)^4. so, guys, everyone who got 11 as a result is correct. The assumption that a banana turned into an apple... isn’t logical.

  • @java1engmervat67
    @java1engmervat67 ปีที่แล้ว

    how can get equation in 10:25?

  • @monaal.8494
    @monaal.8494 6 ปีที่แล้ว +1

    In the second example we can't not to choose from the cheese and the raspberry because then it will be less than seven so shouldn't be like for cheese x+ x²+x³
    And for raspberry x+x²+x³+x4!

  • @chaitanyapr1998
    @chaitanyapr1998 8 ปีที่แล้ว

    *Awesome explanation....*

  • @MarvinOGarza
    @MarvinOGarza 7 ปีที่แล้ว

    Great explanation bro, what's the name of the video where you explain this in more detail? (The following video) Thsnks

  • @Sasquatch4lifeX
    @Sasquatch4lifeX 6 ปีที่แล้ว

    Can we see more of these PLEASE?!

  • @jensenmacneil6914
    @jensenmacneil6914 5 ปีที่แล้ว +1

    Hey Patrick, can you please make a video on exponential generating functions, and also a video on finding the coefficient using polynomial identifies?
    Plz

  • @ostrichparty101
    @ostrichparty101 8 ปีที่แล้ว

    Hi Patrick, do you think it is reasonable to skip a precalculus class at my high school and move from Enriched Algebra 2 & Trigonometry -> AP Calculus AB/BC? Thank you and happy holidays.

    • @blownspeakersss
      @blownspeakersss 7 ปีที่แล้ว

      It could be done. But I'd suggest you take precalculus first. There's no reason to rush things.

  • @cardflopper3307
    @cardflopper3307 6 ปีที่แล้ว

    Hello, how can we find the # of permutations with gen func?... For example set = {GGGBP} how many 2-letter strings can be produced?

  • @lukonikola
    @lukonikola 8 ปีที่แล้ว +1

    When will second part be released?? I have exam soon, so hurry up!!!

  • @Pepe-bg9eg
    @Pepe-bg9eg ปีที่แล้ว

    In the third example, the number to choose is 7. If you not choose any raspberry, the another two types total remaining amount only adds up to five, which is below the number initially stipulated. Then, when performing the numerical check, 3 is set as the maximum amount of raspberries. But it is possible to choose (4,3,0);(4,2,1);(4,1,2). Can someone clarify this doubt for me?

  • @ZelenoJabko
    @ZelenoJabko 8 ปีที่แล้ว +1

    Why would knowing this be beneficial at all? Multiplying those polynomials is similarly computationally expensive than looping over all options. What am I missing?

    • @justinward3679
      @justinward3679 8 ปีที่แล้ว

      Being able to combine generating functions from multiple different problems and save polynomials to come up with quick solutions to potentially difficult problems would be my guess.

    • @alberto3071
      @alberto3071 4 ปีที่แล้ว

      You can reduce to the infinite series, and you gain a lot of computational time. You can write 1+x+...+x^6=
      (1-x^7)/(1-x) for example.

  • @dingshuoyang2421
    @dingshuoyang2421 5 ปีที่แล้ว

    Wait a sec..... thank you for the video but..... how do you do that polynomial multiplication and simplification in one step?

  • @rudycomer8624
    @rudycomer8624 7 ปีที่แล้ว

    I watched this before one of my exams and I wouldn't have gotten one of the questions at all if I hadn't. Thanks!

  • @elementalneil7967
    @elementalneil7967 5 ปีที่แล้ว +1

    how is he expanding those things so fast?

  • @mkutkarsh
    @mkutkarsh 6 ปีที่แล้ว

    Where is the second part?

  • @faridaelgenedi6962
    @faridaelgenedi6962 3 ปีที่แล้ว

    i love you thankyouuuuuuuuuu

  • @abhishekprajapati1504
    @abhishekprajapati1504 8 ปีที่แล้ว

    please make a video on complex numbers

  • @abhinavbajpai795
    @abhinavbajpai795 6 ปีที่แล้ว

    Wow!!

  • @aboutscience3670
    @aboutscience3670 7 ปีที่แล้ว

    Thanks

  • @zizo8737
    @zizo8737 5 ปีที่แล้ว

    How to make that table 😨

  • @احمدعباس-ر9ط8ش
    @احمدعباس-ر9ط8ش 8 ปีที่แล้ว

    thanks😙😙😙😙😙

  • @Nonresponder01
    @Nonresponder01 8 ปีที่แล้ว

    statistical methods seems like the more efficient method.

  • @krishnachaitanyadonkada1185
    @krishnachaitanyadonkada1185 5 ปีที่แล้ว

    You sound like Tarantino :0

  • @altodelia888
    @altodelia888 6 ปีที่แล้ว

    shikachus

  • @ShankyTheBaa
    @ShankyTheBaa 7 ปีที่แล้ว

    so much confusion....