not your AVERAGE Putnam limit (2021 Putnam A2)

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  • čas přidán 25. 06. 2022
  • not your AVERAGE Putnam limit. We evaluate a limit with exponential functions and averages, taken from the William Lowell Putnam Math Competition. This is problem A2 from the 2021 Putnam exam. We do this by taking logarithms, hospital’s rule, derivatives of exponential functions, and the definition of e as a limit. This is a must see for calculus 1 students and anyone interested in math Olympiad problems, enjoy!
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Komentáře • 28

  • @vasuhardeo1418
    @vasuhardeo1418 Před 2 lety +8

    your vids are such fun, great vibes sir.

  • @manwork6545
    @manwork6545 Před 2 lety +3

    Basic stuff but interesting. Especially the use of the l'Hospital rule (not very intuitive...). Thank you Dr Peyam.

  • @olli3686
    @olli3686 Před 2 lety +1

    Love the little Mohawk

  • @Szynkaa
    @Szynkaa Před 2 lety +2

    i did it slightly different- first i took ln(g(x)) as you did, but then i didn't use de"hospital rule- instead i used inequality y/(y+1)

  • @SuperYoonHo
    @SuperYoonHo Před 2 lety +8

    saw this ahter 14 secs it was loaded

  • @SuperYoonHo
    @SuperYoonHo Před 2 lety +3

    also... GREAT VIDEO!

  • @mtaur4113
    @mtaur4113 Před 2 lety +1

    There is a mean value theorem trick for this one, when I saw this problem in a forum thread a while ago. Sadly I was stumped by most of the other problems, maybe I got one of the others right? But Real Analysis 1 is one of my strongest areas. A difference of two things with a "+c" inside the parentheses once suggests MVT!
    A slight change, but I had to save the limits for the end and define (g(x,h))^h = (x+1)^(h+1) - x^(h+1).
    This is equal to f(x+1) - f(x) = f'(x*), for some x* in (x,x+1), where f(x) = x^(h+1). So g(x,h)^h = (h+1)x*^h, and g(x,h) = (1+h)^(1/h)*(x*). x*/x is in the interval (1, 1+1/x), so you can take the limits as h to 0 and x to infinity in that order with a bit of squeeze theorem thrown in.

  • @isimyok5848
    @isimyok5848 Před 2 lety +1

    i like this

  • @harikishan5690
    @harikishan5690 Před rokem

    nice!!

  • @adityaekbote8498
    @adityaekbote8498 Před 2 lety +1

    This was a fun one!

  • @win764
    @win764 Před 2 lety +1

    Does the logistic map recurrence relation have a closed form?

  • @draaagoo7799
    @draaagoo7799 Před 2 lety +1

    yessir

  • @perappelgren948
    @perappelgren948 Před 2 lety +2

    That smile @ 5:00 😆😆😆

  • @iRReligious
    @iRReligious Před 2 lety

    LMAO , that mic🎤 drop at end 🔚 😂😂😂

  • @zeropotential6830
    @zeropotential6830 Před 2 lety

    Sir do you teach at any University?

  • @hccuugxt7cj8jbk9utgx
    @hccuugxt7cj8jbk9utgx Před rokem +1

    شكرا على معلومات 🙋‍♀️🙋‍♀️🙏🙏🙏🙏👈👈👈👈🔔🔔🔔👍👍😥😥😥😥🙏🙏🙏🙏

  • @ready1fire1aim1
    @ready1fire1aim1 Před 2 lety

    We're 4D. Like quaternion math.
    I keep hearing theories like "simulation", "holographic" or back to Leibniz' "contingent" universe.
    Those theories all match the i, j, k in quaternions.
    Quaternion
    MATHEMATICS
    a complex number of the form w + xi + yj + zk, where w, x, y, z are real numbers and i, j, k are imaginary units that satisfy certain conditions.
    RARE/biblical
    a set of four parts, things or persons. (dimensions?)

  • @DavesMathVideos
    @DavesMathVideos Před rokem

    Hello Dr. Peyam, just to let you know, your title is wrong. It should be Question A2. Question A1 is about the grasshopper, which I actually solved over on my channel. It's also a not-to-hard question involving vectors and 3-4-5 right triangles, somewhat easy for a Putnam. Looks like 2021 was an easy year, relatively speaking.
    Your solution by the way is elegant and your explanation is great. As you say, a Calc 1 student can do it if he knows what to look for.

  • @alexdemoura9972
    @alexdemoura9972 Před 2 lety +1

    L'Hôpitalizable...
    😁😁😁😁😁😁

  • @ready1fire1aim1
    @ready1fire1aim1 Před 2 lety

    3 sets of 3 dimensions.
    1D, 2D, 3D are spatial
    4D, 5D, 6D are temporal
    7D, 8D, 9D are spectral
    1D, 4D, 7D line/length/continuous
    2D, 5D, 8D width/breadth/emission
    3D, 6D, 9D height/depth/absorption

  • @giorgibliadze1151
    @giorgibliadze1151 Před 2 lety +1

    Doctor! Please show some respect and do proper hornes)))), not some spider man ))))