A Math Olympiad| Challenging exponential question| solve 2²² - 1

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  • เผยแพร่เมื่อ 25 ต.ค. 2024

ความคิดเห็น • 42

  • @xiangge6374
    @xiangge6374 2 หลายเดือนก่อน +3

    this is an example of how to make a complicated solution for simple question.

  • @KipIngram
    @KipIngram หลายเดือนก่อน

    Ok. So 2^22 is 2^11 squared. 2^11 = 2048. So, picture a square grid, 2048 by 2048. First take care of the 2000 by 2000 part - that's 4,000,000. Then add 2*2000*48 = 192,000, so we're up to 4,192,000. That leaves a 48 by 48 grid in the top right corner to cover. Let's add a 50 by 50 grid instead, which adds 2,500, so we're up to 4,194,500. Now subtract the two extra rows and the two extra columns - 100 each. So 4,194,300. Finally, add back the 2 by 2 grid we subtracted twice, so 4,194,304. Finally, subtract the 1. 4,194,303. Q.E.D.
    You can do this in your head if you can hold a couple of numbers in memory, and you can ABSOLUTELY do it on scratch paper in under a minute.

  • @yvesdelombaerde5909
    @yvesdelombaerde5909 2 หลายเดือนก่อน +5

    2^22 is 2^10 x 2^12 = 1024 x 4096 which is quite easy by hand, then subsract 1

  • @beragis3
    @beragis3 2 หลายเดือนก่อน

    Anyone who has done a lot of programming and worked in binary and hexadecimal can go through powers of two in seconds. A few common powers known for memory are 2^10 = 1024 or 1K and 2^20 = 1049576 or 1M, So multiply 2^20 by 4 and subtract 1 you get 4194303. You would think by now the Math Olympiad wouldn't use this type of question.

  • @roshlew6994
    @roshlew6994 2 หลายเดือนก่อน +1

    2^22 = (2^10)^2 x 2^2

  • @JimohRidwanullah
    @JimohRidwanullah 2 หลายเดือนก่อน

    You're always doing great...
    And make mathematics simplest

  • @sie_khoentjoeng4886
    @sie_khoentjoeng4886 2 หลายเดือนก่อน +1

    The well known of "2 power N", for large N in infornation system is 256 (2^8,, 8-bit), 1024 (2^10, kilobyte), 65.536 (2^16, 16-bits), and 16.777.216 (2^24, 24-bits, RGB color)..
    So,
    2^22 - 1
    = 2^16 x 2^6 - 1
    = 65.536 x 64 - 1

    • @JJONLINEMATHSCLASSchannel
      @JJONLINEMATHSCLASSchannel  2 หลายเดือนก่อน

      Nice but calculator is not allowed

    • @MrQuantumIguana
      @MrQuantumIguana 2 หลายเดือนก่อน

      No calculator needed. Just paper and pencil .​@@JJONLINEMATHSCLASSchannel

  • @Psykolord1989
    @Psykolord1989 2 หลายเดือนก่อน +2

    Before watching:
    2^22 -1 = (2^11 +1)(2^11 -1)
    2^11 = 2048, so this is (2049)(2047)
    = 14343
    + 81960
    + 000000
    + 4098000
    = 96303+4098000 = 94303+4100000 = 4194303
    Alternatively: Know your powers of 2. (Admittedly that's a bit difficult to know them up to the 22nd power)

  • @renatootaviosilvafranco5704
    @renatootaviosilvafranco5704 2 หลายเดือนก่อน

    I did it another way, but it also works. Thank you teacher.
    2^22 - 1 =
    2^5 x 2^5 x 2^5 x 2^5 x 2^2 - 1 =
    32 x 32 = 1024 x 32 = 32768 x 32 = 1048576 x 4 = 4194304 - 1 = 4194303

  • @devonwilson5776
    @devonwilson5776 2 หลายเดือนก่อน

    Greetings. Thanks always for sharing. That was a very good exercise. Mentally, we could determine the value of 49 times 47 by considering base 40 times 56, the sum of 49 and 7 or 47 and 9, plus 9 times 7. That is (40×56)+(9×7)=
    2240+63=2303.

  • @jerrypaquette5470
    @jerrypaquette5470 2 หลายเดือนก่อน +3

    2^22 = (2^11)^2
    2^11 = 2048
    It's not that difficult toto multiply 2048 x 2048 = 4194304
    than subtract 1 you get 4194303

  • @RyanLewis-Johnson-wq6xs
    @RyanLewis-Johnson-wq6xs 2 หลายเดือนก่อน +1

    I don’t have to think about it.

  • @anandan-buree
    @anandan-buree 2 หลายเดือนก่อน

    2^22=2^11*2
    =2048^2
    =2048*2048
    =4194304
    2^22-1=4194304-1
    =4194303

  • @ichdu6710
    @ichdu6710 2 หลายเดือนก่อน

    normal calculation
    2^10 =1024
    you multiply that with 2 until 2°22 is arrived.

  • @georgejo7905
    @georgejo7905 หลายเดือนก่อน

    Binary 2^22 = 1000000000000000000000 - 1 = 1111111111111111111111

  • @RealQinnMalloryu4
    @RealQinnMalloryu4 2 หลายเดือนก่อน

    2^11 ➖ 1 2^11^1 ➖ 1 2^1^1 ➖ 1 21 (x ➖ 2x+1).

  • @สุนทรราชวงศ์ศึก
    @สุนทรราชวงศ์ศึก 2 หลายเดือนก่อน

    Thank you, mam, I am stupid in mathematics. I would get better from now on.

  • @peterbrown2882
    @peterbrown2882 2 หลายเดือนก่อน

    2 to the nth power being 22. 2x10 = 20 (2x2) = 4 (2x2x2) = 8 now we have 2048 2048x2048 = 4194304 You cannot end it with a 3 in anyones mathamatical language. Your method is far too complcated. Imagine having to memorise all those steps. Oh boy !!!!! CRAZY is Right 😂😂😂😂😂

  • @dylingadhal5762
    @dylingadhal5762 2 หลายเดือนก่อน

    483

  • @paulolemosmessias9460
    @paulolemosmessias9460 2 หลายเดือนก่อน

    Muito linda esta mulher

  • @wilsonfrye9987
    @wilsonfrye9987 2 หลายเดือนก่อน

    😅2^22-1=4(10^3+24)(10^3+24)-1=4(10^6+4.8x10^4+.0576x10^4)-1=4(1.048576x10^6)-1=
    4194303

  • @RyanLewis-Johnson-wq6xs
    @RyanLewis-Johnson-wq6xs 2 หลายเดือนก่อน +1

    2^22-1=4194303 Final Answer JJ

  • @reinhardtristaneugen9113
    @reinhardtristaneugen9113 2 หลายเดือนก่อน

    it is < 4 194 303 > and done in no time, what is not all too crazy, since up to 2^30, I got the numbers all stored in my mind.
    Le p'tit Daniel

  • @ghamoz
    @ghamoz 2 หลายเดือนก่อน +1

    Alla fine è solo fare una moltiplicazione che stronzata