Asked the lovely lady at my school's library for the wifi password. She pointed me to this integral.

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  • Опубликовано: 2 фев 2025

Комментарии • 249

  • @bprpcalculusbasics
    @bprpcalculusbasics  11 месяцев назад +43

    When your calculus test has only one problem: ruclips.net/video/wyORoB5Q2Hg/видео.htmlsi=NQptnwoGli9NPji-

    • @JP-yu1qc
      @JP-yu1qc 11 месяцев назад +1

      It's a differential equation because they have sqrt of dx.

  • @mateoarteaga8274
    @mateoarteaga8274 11 месяцев назад +450

    I love how they expect you to be smart enough to do it but they can't be smart enough to put the dx outside of the square root

    • @karthikeyank132010
      @karthikeyank132010 11 месяцев назад +119

      No one said the questioner was smart. Also the confounding "first digits" - first how many digits?

    • @kouhaiii3182
      @kouhaiii3182 10 месяцев назад

      ​@@karthikeyank132010wifi passwords require a minimum of 8 characters. i would assume the first 8 digits of pi

    • @jenniferpearce1052
      @jenniferpearce1052 10 месяцев назад +4

      That was the first thing I noticed!

    • @MirlitronOne
      @MirlitronOne 10 месяцев назад

      Nobody likes a smart arse.

    • @andrewcuber8968
      @andrewcuber8968 10 месяцев назад +10

      @@karthikeyank132010 they should've just said all of the digits lol

  • @Ethanium
    @Ethanium 11 месяцев назад +530

    Luckily, they didn't ask for the last digits of the result 😅

    • @MrYerak5
      @MrYerak5 10 месяцев назад +1

      "The last digit is one" Apo

  • @Ninja20704
    @Ninja20704 11 месяцев назад +754

    I love how in the end you were reading pi in chinese.

    • @alinaqirizvi1441
      @alinaqirizvi1441 11 месяцев назад +82

      I think he has it memorised in Chinese

    • @Mike__B
      @Mike__B 11 месяцев назад +51

      I noticed that too, my wife says she does counting like that in her head something about being able to visualize it better and she's been in the US since she was 7 years old. FYI, that as Mandarin... as counting to 10 in Mandarin is the only Mandarin I really know, well that and thank you shi-shi :)

    • @alinaqirizvi1441
      @alinaqirizvi1441 11 месяцев назад +19

      @@Mike__B *xiexie

    • @Mike__B
      @Mike__B 11 месяцев назад +12

      @@alinaqirizvi1441 Thanks, I was more spelling it phonetically since in the English language we really do that kind of sound with x's

    • @Hahahahaaahaahaa
      @Hahahahaaahaahaa 11 месяцев назад +5

      Japanese and Chinese digit memorization is much easier than in English.

  • @unclebrat
    @unclebrat 10 месяцев назад +194

    They want the first digits but don't tell you how many digits you need.

    • @crysta11ikzxc
      @crysta11ikzxc 10 месяцев назад +26

      most wifis require at least 8 symbols in password so i think 3.1415926 would be right
      edit: the pass is 31415926

    • @kaballfs
      @kaballfs 10 месяцев назад +23

      As someone on reddit pointed out, it's just a brute force problem, put in digits of pi until it works.

  • @ChonkyBear299
    @ChonkyBear299 10 месяцев назад +43

    Old lady: *points toward sign*
    Me: "sigh", *opens up photomath*

    • @lorddarthvader6289
      @lorddarthvader6289 10 месяцев назад +5

      I was also thinking of a graphing calculator, but that's even faster lol.

  • @Virtuoso866
    @Virtuoso866 11 месяцев назад +187

    The moment I saw the -2 to 2 I was like "yep, odd function to make the problem look harder than it is"

    • @g_g...
      @g_g... 11 месяцев назад

      Do they cancel out?

    • @Gulyus
      @Gulyus 10 месяцев назад +18

      Yeah one of the terms @@g_g... completely cancelled out because the -2 to 0 and the 0 to +2 portions are equal and opposite. X^3 cos(x/3) term is odd * even and is 0 over the range so that portion becomes 0.

    • @g_g...
      @g_g... 10 месяцев назад +12

      @@Gulyus I'm gonna pretend like I understood most of it

    • @kingacrisius
      @kingacrisius 10 месяцев назад +9

      @@g_g... Integration can be thought of as the total area under the curve between the numbers given, in this case -2 and 2. Any part where the line goes into the negatives is subtracted from the area. Since the function is exactly mirrored over the origin, the part to the left of zero is opposite of the part on the right. It ends up being like x - x, which is zero no matter what x is. So we don't even have to do the math to determine x, we just know the result of x - x is zero.

    • @g_g...
      @g_g... 10 месяцев назад +3

      @@kingacrisius right, I understand that concept very easily, but I don't understand the mathematical terms and concepts mentioned within the explanation. It's like writing an entire paragraph on why 1 + 1 equals 2. I'm also not familiar with like two of the symbols in the equation, so that might explain why I'm a bit lost on some of the concepts.
      So basically, you have to combine those two numbers. In this case turning into zero, so then that big symbol ends up dissappearing? Or did I just spout a bunch of nonsense? And why is it put like that?I find it hard to believe that two numbers that you simply have to combine will be put in such a frightening format. I am definitely missing something

  • @ssifr3331
    @ssifr3331 11 месяцев назад +184

    when there is a puzzle/question like that, the answer is most likely pi or e. Try both first, if both fails, time to do some maths lol.

    • @2045-z6o
      @2045-z6o 11 месяцев назад +7

      Then try sqrt(pi) and sqrt(e)

    • @pseudo_goose
      @pseudo_goose 11 месяцев назад +6

      Or tau

    • @PM-wt3ye
      @PM-wt3ye 10 месяцев назад

      @@2045-z6oHow to type in 8 digits from sqrt of pi or e? 🤔

    • @KP-ty9yl
      @KP-ty9yl 10 месяцев назад +11

      in calculus we had online homework with unlimited tries and I would always try pi, 0, and 1 first

    • @Mark73
      @Mark73 10 месяцев назад +1

      Yeah, but to how many decimal places?

  • @WideCuriosity
    @WideCuriosity 10 месяцев назад +36

    The least they should have given should include how many first digits.
    No wonder my '3' didn't work !

    • @libredove
      @libredove 10 месяцев назад

      I'm sure that the shortest WPA2-PSK password is 8 characters long.

  • @decaydjk8922
    @decaydjk8922 11 месяцев назад +11

    As other people have noted: Engineer's answer, it's going to be pi because that's the only "important" constant most people know. That was fun though, doing integration without doing any standard "mechanical" integration, all reliant on understanding properties of the functions being integrated.

  • @christianvanderstap6257
    @christianvanderstap6257 11 месяцев назад +57

    I really really need to start to learn some math again.

    • @paultapping9510
      @paultapping9510 11 месяцев назад +7

      khan academy is free and great.

    • @ipsojure2137
      @ipsojure2137 11 месяцев назад +2

      yeah man. really couldn't solve this one

    • @bombintheseeinq
      @bombintheseeinq 10 месяцев назад

      aops textbooks ftw

    • @Oberstien17
      @Oberstien17 10 месяцев назад

      It's really hard tho​@@ipsojure2137

  • @white_145
    @white_145 10 месяцев назад +8

    My immediate reaction to these riddles would be to guess pi and e. So cool to see it actually can work out

  • @unrealuknow864
    @unrealuknow864 10 месяцев назад +10

    "I am premed. Can you just give me the password? "

    • @8bits59
      @8bits59 10 месяцев назад

      Chem TA here. I hate this with every fiber of my being.

  • @Wmann
    @Wmann 10 месяцев назад +7

    So relatable when you can’t help but count in Chinese if you grew up with it… I literally have the multiplication table memorised in Chinese.

    • @carultch
      @carultch 10 месяцев назад

      It's a much more civilized language for naming numbers. You can learn just the numbers 1 thru 10, and count all the way to 99, without learning anywhere near as many irregularities as English.
      Examples:
      The inconsistent spellings of one, two and eight, that don't reflect their pronunciation
      Eleven & twelve, instead of fitting the pattern of the teens
      The one's place coming first for all the teens; a holdover from the reversed order of German two-digit number names
      The fact that teens are even called teens in the first place, instead of "wunty wun" thru "wunty nine".
      The fact that four has a u, and forty doesn't
      The fact that the first syllable of fifty doesn't rhyme with five
      All of these problems go away, in the Chinese number naming system

  • @engineer-rs2ev
    @engineer-rs2ev 11 месяцев назад +5

    4:40 you remembered your childhood origins

  • @justincronkright5025
    @justincronkright5025 11 месяцев назад +1

    4:48 - well at least I caught you right at the end there...
    No good to bring back the maths memories, every little hint helps put all of the pieces back into place!

  • @TechSY730
    @TechSY730 11 месяцев назад +26

    If dx _was_ inside the sqrt, would you need to do a u-substitution to extract any sense out of this formula?

    • @dougsmith5873
      @dougsmith5873 11 месяцев назад +4

      I was lost at that point. When I saw dx outside, I got the even/odd thing.

    • @nutronstar45
      @nutronstar45 11 месяцев назад +4

      i think if the dx is inside the root the integral would blow up to infinity

    • @professorhaystacks6606
      @professorhaystacks6606 10 месяцев назад +4

      In this particular case the problem wouldn't be defined as the differential would only be applied to part of the term, so there would be no clear integration differential for the rest (yes I'm over-simplifying). I'm simplifying a bit as technically the square root isn't strictly speaking separable in terms like that, but you have a differential so you can do a binomial expansion and drop higher terms in dx. If you had sqrt(dx) outside, there are ways to do it, but it gets messy. That sort of thing shows up in relativity and advanced geometry as the differential interval involves a square root.

    • @tobybartels8426
      @tobybartels8426 10 месяцев назад

      ​@@professorhaystacks6606: You can make sense of the Riemann integral of _any_ expression involving x and dx (barring issues like division by zero) by dividing [−2,2] into subintervals, picking a point in each subinterval, evaluating the expression on each tagged subinterval using the point as x and the subinterval's width as dx, adding these up, and taking the limit as the largest subinterval's length approaches zero, if this limit exists. (A more sophisticated limit can define the Lebesgue or Henstock-Kurzweil integral.) In this case, since the integrand doesn't approach zero as dx does, the limit will be infinite (really +∞ from about −0.8 to 2 and −∞ from −2 to about −0.8). But even the integral of √dx would be infinite (since the integrand approaches zero too slowly), while the integral of dx² will be zero (since the integrand approaches zero too quickly). On the other hand, there are useful expressions in a multivariable context, such as √(dx²+dy²+dz²−dt²), that give nontrivial results.

  • @carultch
    @carultch 11 месяцев назад +15

    Open Excel. Assign dx = 0.0001, and assign a name to make an absolute reference to it.
    Set Column A for x from 0 to 1. Set up Column B for the x-values at the midpoint between each pair of x-values in column A.
    Set up Column C to evaluate the integrand as a function of each Column B x-value. Add up all column C-values, and you have a numerical approximation to the solution, using the Midpoint Rule for Riemann Sums.

    • @Qermaq
      @Qermaq 11 месяцев назад +5

      Can you explain how to do step one? Creating a named variable in Excel.

    • @carultch
      @carultch 11 месяцев назад

      @@Qermaq Select the cell you want to name. Look for its ID in the upper left, next to the formula bar. This is a text field, where you can type in a custom name for making an absolute reference to that cell. You can also use the name manager. For instance, you can type 9.8 in a cell, and then g in that text field. From then on, you can refer to g in a formula, and it will fix the reference to that cell as a constant.
      Some names are off-limits, so you can't use c or r for instance (which are hotkeys for selecting column and row respectively), or anything else that is reserved. You'd need to use c_ or r_, if it is natural for you to call your variable c or r. If you want a number subscript after the letter, you can use the underscore to indicate a subscript.

  • @Qermaq
    @Qermaq 3 месяца назад +2

    "What motivated your approach?" "I wanted to watch cat videos."

  • @kujmous
    @kujmous 11 месяцев назад +19

    I thought that first part looked a bit odd.

    • @Livio_05
      @Livio_05 10 месяцев назад

      i see what you did there

  • @_HAKSOZ
    @_HAKSOZ 11 месяцев назад +57

    Why is odd × even × even function = odd function?

    • @cyrusyeung8096
      @cyrusyeung8096 11 месяцев назад +71

      Because you have 1 negative sign from the odd function only. Complete proof:
      Suppose f is odd function, and g, h are even functions.
      Let z(x) = f(x)g(x)h(x), then:
      z(- x)
      = f(- x)g(- x)h(- x)
      = - f(x)g(x)h(x)
      = - z(x)

    • @bprpcalculusbasics
      @bprpcalculusbasics  11 месяцев назад +91

      Say o(x) is odd and e(x) is even.
      By def, we have o(-x)=-o(x) and e(-x)=e(x)
      Then we see o(-x)e(-x)*e(-x)=-o(x)e(x)e(x). the result is odd.

    • @_HAKSOZ
      @_HAKSOZ 11 месяцев назад +9

      Thank you

    • @iyziejane
      @iyziejane 11 месяцев назад +1

      Edit: I said something mistaken that was corrected below, just editing to not waste anyone's time.

    • @cyrusyeung8096
      @cyrusyeung8096 11 месяцев назад +1

      @@iyziejane No, odd no. * even no. * even no. is even. For example, 3 × 2 × 4 = 24, which is even. Some say odd functions are given its name because x^n is odd if n is odd.

  • @robertpearce8394
    @robertpearce8394 11 месяцев назад +64

    "How I need a drink, alcoholic of course, after the heavy chapters involving quantum mechanics" gives pi to 14 decimal places. What were you using?

    • @carultch
      @carultch 11 месяцев назад +36

      Speaking of drinks and the premise of this video:
      A guy walks into a bar, and sits down at the counter, and asks for the wifi password. The bartender replies, "please buy a drink first".
      The man pays, and the bartender serves the guy the drink. The guy then asks for the wifi password again. The bartender replies, "pleasebuyadrinkfirst, all one word, all lowercase".

    • @alinaqirizvi1441
      @alinaqirizvi1441 11 месяцев назад +3

      I think he just had it memorised in Chinese

    • @CST1992
      @CST1992 11 месяцев назад +2

      I just have it memorized from Wikipedia. 3.14159265358979... what do we know, that's the exact one you have!

    • @CST1992
      @CST1992 11 месяцев назад +2

      @@carultch That's savage

    • @padfoot9445
      @padfoot9445 11 месяцев назад

      ​@@CST1992 I had a "Help your kids with maths" book when I was a kid; the front cover was like 200 digits of pi, so I memorized
      3.1415926535897932384

  • @patsk8872
    @patsk8872 11 месяцев назад +4

    Differential inside the square root, confiscate the router

  • @cyrusyeung8096
    @cyrusyeung8096 11 месяцев назад +14

    The video suddenly stops. I suspect that you might have accidentally trimmed away part of the video.

    • @wuhoolife
      @wuhoolife 11 месяцев назад +1

      Probably because you were too early right after the upload.

    • @bprpcalculusbasics
      @bprpcalculusbasics  11 месяцев назад +40

      No. I just did that on purpose.

    • @cyrusyeung8096
      @cyrusyeung8096 11 месяцев назад +2

      @@bprpcalculusbasics I see. Thank you for your reply.

    • @canyoupoop
      @canyoupoop 11 месяцев назад

      4:55 is a nice number

    • @arpitbanka767
      @arpitbanka767 11 месяцев назад

      Your comment shows a day ago. How TF is this possible? ​@@cyrusyeung8096

  • @ssgamer5693
    @ssgamer5693 11 месяцев назад +6

    Why dx outside the sqrt?
    Give solution for dx inside the sqrt❤

    • @lazy_biscuits08
      @lazy_biscuits08 11 месяцев назад +4

      It's not possible, dx represents smallest increments which form area under f(x). It has to be dx not sqrt(dx), you can't integrate it otherwise.

    • @raja2850
      @raja2850 11 месяцев назад

      ​@@lazy_biscuits08root dx is greater than dx.

  • @game__r
    @game__r 11 месяцев назад +4

    this guy makes this shit look to easy

    • @bladeiron
      @bladeiron 10 месяцев назад

      Because it's not actual computation, it mostly requires quite a bit of mental gymnastics. The average person probably would not have seen the bounds and thought, "hmm yes, is the integrand even or odd?"

  • @bubalubagus7037
    @bubalubagus7037 11 месяцев назад

    oh i did this one a few days ago, cool to see you doing it now

  • @DhDhShah007
    @DhDhShah007 10 месяцев назад +1

    You took this question from a video of BHANNAT MATHS, right??😅😅

  • @whyher229
    @whyher229 11 месяцев назад +2

    I feel like I watched this before in your original channel

  • @bubalubagus7037
    @bubalubagus7037 11 месяцев назад +6

    damn i wish i thought of the first integrand being symmetrical. I ended up doing a taylor series approximation for it which took forever. :(

    • @professorhaystacks6606
      @professorhaystacks6606 10 месяцев назад +1

      Yeah but it works. You want it done fast or do you want it done right? :P

  • @doveShampoo1111
    @doveShampoo1111 10 месяцев назад

    Now we have to ask how many significant figures

  • @aliaujla-2ujt
    @aliaujla-2ujt 11 месяцев назад +2

    dx is under the integral!

  • @cristianemontagner9616
    @cristianemontagner9616 10 месяцев назад +1

    At that point, turn on mobile data and put this on a calculator

  • @striderskorpion
    @striderskorpion Месяц назад

    First digits of the answer is pretty vague. How many digits do they want? Surely it's not just 3. This problem would have been useful for showing trig substitution and trig power reduction formulas.

  • @keyan1219
    @keyan1219 7 месяцев назад

    something im confused at is when integrating the symmetric curve of the odd function why do you apply the concept of negative area? so it would be 2x the integral from 0 to 2 or is negative area only really applied when you are asked to find the magnitude of the area in a certain scenario and you arent taking into things like a negative direction?

  • @weeblordgaming6062
    @weeblordgaming6062 11 месяцев назад +3

    People with a ti84
    I don’t have such weaknesses

  • @tobybartels8426
    @tobybartels8426 10 месяцев назад

    Since the differential is inside the square root, the value of the integral is infinite.

    • @tobybartels8426
      @tobybartels8426 10 месяцев назад

      (Really +∞ where the integrand is positive, from about −0.8 to 2, and −∞ where the integrand is negative, from −2 to about −0.8, giving no overall value.)

  • @tastyl2356
    @tastyl2356 11 месяцев назад +2

    the dx was in the square root ???

    • @upstander1233
      @upstander1233 11 месяцев назад +2

      I believe he mentioned that it wouldn’t be possible if it was during the first like 30 seconds of the video

    • @tastyl2356
      @tastyl2356 11 месяцев назад

      @@upstander1233 ah yeah i didn't watch most of the vid lmao

  • @pkuvincentsu
    @pkuvincentsu 11 месяцев назад +3

    Haha yes! I can do everything else in my head in English with ease, but numbers, have to do them in Chinese. The brain is weird in that way.

  • @Sg190th
    @Sg190th 11 месяцев назад

    I almost forgot you did this years ago.

  • @akosibrothercoolpzzle123
    @akosibrothercoolpzzle123 22 часа назад

    Where's the problem that Euler's no. Is the answer?

  • @siliconhawk
    @siliconhawk 10 месяцев назад

    plot twist. the password is the question but in string format.
    "integral -2 to 2 (x^2 cos x/2....."

  • @divyamkumar1339
    @divyamkumar1339 11 месяцев назад +1

    Why does the square root include the "dx" in the poster?

    • @jk-2053
      @jk-2053 11 месяцев назад +12

      Probably a typo. That or the person who typed it out looked up this problem online and didn't think dx in the sqrt was strange.

  • @GFlCh
    @GFlCh 11 месяцев назад +7

    "The Wi-Fi password is the **FIRST DIGITS** of the answer"
    How evil is that... ? ... What does she mean by "FIRST DIGITS"? I guess it will be some fixed number if digits, but how many? 1?, 12?, 100? more?
    And, include the decimal point (which is not a digit)?

    • @nyandyn
      @nyandyn 11 месяцев назад +1

      A WPA preshared key is eight characters minimum, so most likely you'll stop immediately when the OK button is no longer grayed out.

  • @Colour_beaks
    @Colour_beaks 10 месяцев назад

    Time to integrate into wifi systems

  • @Bluhbear
    @Bluhbear 11 месяцев назад +1

    It's a bit tricksy that the sign doesn't say how many digits you need for the password.

    • @nyandyn
      @nyandyn 11 месяцев назад

      Eight is the minimum so you'd most likely stop there.

  • @gurjotdosanjh7828
    @gurjotdosanjh7828 11 месяцев назад

    I get that it is even. But how would you know that there is symmetry without looking at the graph? Like what if the function did some funky stuff in the middle?

    • @gurjotdosanjh7828
      @gurjotdosanjh7828 11 месяцев назад

      *odd

    • @Gurogun
      @Gurogun 11 месяцев назад

      can you write an example of an odd function that isn't symmetrical about the origin? I actually don't get what you mean, how can it be odd and not be symmetrical?

    • @bombintheseeinq
      @bombintheseeinq 10 месяцев назад

      funky stuff only happens if it diverges, i believe

    • @bladeiron
      @bladeiron 10 месяцев назад

      Symmetry about the origin is the definition of an odd function.

  • @KYSheng
    @KYSheng 10 месяцев назад

    It surprised me when you recited pi in chinese because I did the same too lmao

  • @ColinRichardson
    @ColinRichardson 11 месяцев назад

    HA! I knew it would be Pi from the thumbnail.. (No, I am not smart enough to work it out, was a total guess, but with it being a library, I knew it would be)

  • @tgnuelakes
    @tgnuelakes 10 месяцев назад

    Wi-Fi password needs at least 8 symbols. It said just first few numbers, means it should be an irrational number. It have to be easy to remember for frequent users, it should be a famous number without further calculations. So pi, e and sq root 2 become very sus.

  • @bite-sizedshorts9635
    @bite-sizedshorts9635 10 месяцев назад

    It's hard to do calculus when your school never taught it. I didn't have any calculus until I went to college. High school just had algebra and geometry.

  • @rocksalt636
    @rocksalt636 10 месяцев назад

    4 digit password? That’s only 10,000 possibilities, could brute force it very quickly

  • @VectoRaith
    @VectoRaith 11 месяцев назад +7

    So, you need to write the entire answer sequence as the password 😂?

    • @BryanLu0
      @BryanLu0 11 месяцев назад +1

      Usually it's 8 or 10 digits, it seems whoever wrote this sign forgot to specify

    • @diamond_player
      @diamond_player 11 месяцев назад +1

      @@BryanLu0no they did specify it is the first digit so just 3.

    • @BryanLu0
      @BryanLu0 11 месяцев назад +5

      @@diamond_player Actually, it says "first digits" not "first digit"

    • @eltrick__
      @eltrick__ 10 месяцев назад

      additionally, wifi passwords are required to have a minimum of 8 characters anyway...

  • @pUteRIsms_
    @pUteRIsms_ 10 месяцев назад

    Tried inputing this in my calculator, i think i fried it

  • @lunstee
    @lunstee 11 месяцев назад

    You're almost a week early for this one!

  • @Barreloffish
    @Barreloffish 11 месяцев назад

    So what is the password? I need access to the Wi-Fi.
    "The Wi-Fi password is the first digits of the answer"
    First how many digits? It doesn't say. If it is "first digit" (one digit number) and not digits, then you don't even need calculus to find out. However, it doesn't tell you how many digits are the password. Still have to do the check and error method?

    • @VORASTRA
      @VORASTRA 10 месяцев назад

      Most likely 8 since it is the minimum amount of symbols in the password

  • @Heisemberg08
    @Heisemberg08 11 месяцев назад +1

    Odd functions f(-x) = f(x), so the integral is zero. Good.

  • @adenwellsmith6908
    @adenwellsmith6908 10 месяцев назад

    dx under the square root?

  • @chrisf5418
    @chrisf5418 10 месяцев назад +4

    I would've brute-forced it: there are only 10 possible passwords regardless of the integral.

  • @lanzji1345
    @lanzji1345 11 месяцев назад +3

    The most difficult part is: how many digits is "the first digits"?
    For the result, I agree, the answer is either π or e, or maybe √2. There's a cos in there, so it's most probably π.

    • @galoomba5559
      @galoomba5559 11 месяцев назад +1

      the π doesn't come from the cos though

    • @Fixnown
      @Fixnown 11 месяцев назад +1

      how do oyu get a pi if you integrate cos?

    • @tacthib1396
      @tacthib1396 11 месяцев назад +1

      The cos doesn't do anything

    • @KaikyAlmeida-b8t
      @KaikyAlmeida-b8t 11 месяцев назад

      Password fields usually require a minimum amount of digits from the user, so those are the first digits

    • @nyandyn
      @nyandyn 11 месяцев назад

      @@KaikyAlmeida-b8tYes. Eight in WPA.

  • @Ortagonation
    @Ortagonation 10 месяцев назад

    the problem the password is π , pi, pie, 22/7, 22:7, or 3.14.....

  • @fraz071097
    @fraz071097 10 месяцев назад

    It's wrong because also the dx was inside the square root

  • @hypercoder-gaming
    @hypercoder-gaming 11 месяцев назад

    For the fist half of the integral, shouldn't you split it into -2->0 and 0->2 since negative area doesn't exist?

    • @panda4247
      @panda4247 11 месяцев назад

      It's not "negative area" per sé, it's area that is substracted from the area above the curve

  • @kyokazuto
    @kyokazuto 10 месяцев назад

    I'm just glad I have data

  • @IgnoredJoel
    @IgnoredJoel 11 месяцев назад +1

    [I AM WRONG] The correct answer for the integral is 2 π, you applied 1/2 twice.

    • @robertpearce8394
      @robertpearce8394 11 месяцев назад +1

      Remember that there is a factor of 1/2 outside the integral. Make that 1, and you get 2pi or tau. Then you can have the argument about which is better.

    • @IgnoredJoel
      @IgnoredJoel 11 месяцев назад

      @@robertpearce8394 My bad, forgot about this one 😅

  • @Leo__2005
    @Leo__2005 11 месяцев назад

    Laughs in scientific calculator 🤣

  • @dd661
    @dd661 10 месяцев назад

    Me solving without using pen in just 1.5 minutes

  • @kingacrisius
    @kingacrisius 10 месяцев назад

    Why tf is the dx inside of the square root?

    • @kingacrisius
      @kingacrisius 10 месяцев назад

      Lol you mentioned that immediately

    • @kingacrisius
      @kingacrisius 10 месяцев назад

      They also didn't even say how many digits it was, just "the first digits"

  • @ibrahimhammoudeh7153
    @ibrahimhammoudeh7153 11 месяцев назад

    I got this equation on my calc 1 final

  • @Ozasuke
    @Ozasuke 11 месяцев назад

    So is the wifi password "pi" or some undefined number of digits of pi?

    • @gasparsigma
      @gasparsigma 10 месяцев назад

      It says first digits, but it doesn't say how many. Could be the first 8, could be the first 389492875929 digits

    • @NowWeJustWinIt
      @NowWeJustWinIt 10 месяцев назад

      ​@@gasparsigmaehh... it can be anything between 8 and 63, longer passwords aren't allowed as per WPA spec, but hey just saying some random large number is funnier

  • @jinbeisallblue9016
    @jinbeisallblue9016 10 месяцев назад

    i would have tried 'pi' before doing any of this honestly...

  • @johnwick7175
    @johnwick7175 10 месяцев назад

    I hate with a passion when the lecturer writes stuff like sin x/2 + 3 or something like it instead of sin(x/2) + 3 or sin(x/3 +3). Just write the damn parentheses ffs. I hate guessing what it's supposed to be.

  • @abj136
    @abj136 11 месяцев назад +1

    password: enter this expression using Latex

  • @daveduvergier3412
    @daveduvergier3412 11 месяцев назад +2

    This is a technique that should be taught more widely - integration by not integrating !

  • @R.F.9847
    @R.F.9847 10 месяцев назад

    Is it just me, or did you just gloss over how the first part of the integral is zero?

  • @SandraMarkusTrachsel
    @SandraMarkusTrachsel 11 месяцев назад

    But, but, but.... what is the password now? I mean, what do you actually type in into the passwort box?

    • @remus_lupin
      @remus_lupin 11 месяцев назад +1

      As many digits of π as the password needs. The sign specifies just the first digits. So, it's probably just "314".

    • @DimaMuskind
      @DimaMuskind 11 месяцев назад

      ​@@remus_lupinI think Wi-Fi password cannot be this short, must be first 8 digits

  • @earlzeller3015
    @earlzeller3015 11 месяцев назад +1

    So, only calculus students get to use the library🤫

  • @themadmallard
    @themadmallard 10 месяцев назад

    Fuji Speedway?

  • @msscoventry
    @msscoventry 3 месяца назад

    Great thumbnail.

  • @jeffreythia4527
    @jeffreythia4527 4 месяца назад

    4:48 Chinese
    SINGAPOREAN DETECTED!!!

  • @spicca4601
    @spicca4601 11 месяцев назад

    ....so it means that the password has an infinite length......really!?

    • @bobh6728
      @bobh6728 11 месяцев назад

      It said first digits, but not how many.

    • @ZipplyZane
      @ZipplyZane 11 месяцев назад +1

      IIRC, the original sign said it was the first 10 digits of the number.

  • @Khantia
    @Khantia 10 месяцев назад

    Hahaha! Even if you solve this, you still have no idea what the password actually is. Do you include the decimal point? How many digits do you use? It's still a guess work xP

  • @QSBraWQ
    @QSBraWQ 11 месяцев назад

    Говорили же что тригонометрия пригодртся.

  • @theeraphatsunthornwit6266
    @theeraphatsunthornwit6266 10 месяцев назад

    Password has one digit
    Can i just try 0 to 9 ....

  • @msolec2000
    @msolec2000 11 месяцев назад

    That song helped... 3.14159265358979323846264338327950288419716939937510582097494459

  • @Maths679
    @Maths679 11 месяцев назад

    Sir where do you belong from?

  • @beranikotor7197
    @beranikotor7197 10 месяцев назад

    Just try 1 to 10 it's much faster. 🎉

  • @UnknownGhost97
    @UnknownGhost97 11 месяцев назад

    This question was already done and given to China students for wifi connection 2 years back

  • @CommandoBlack123
    @CommandoBlack123 11 месяцев назад +1

    I think it would just be faster to brute force the password using only numbers as input

  • @senhueichen3062
    @senhueichen3062 10 месяцев назад

    Pretty easy!

  • @jamegumb7298
    @jamegumb7298 10 месяцев назад

    Plot twist: dx _should_ be inside root not after.

    • @friedrichmyers
      @friedrichmyers 10 месяцев назад

      Then it is not integrable. Not even by wolframalpha I suppose.

  • @logz3288
    @logz3288 11 месяцев назад

    desmos works offline i believe, ez clap

  • @Atilolzz
    @Atilolzz 10 месяцев назад

    I am glad online integration websites do it for you Lel

  • @onx99
    @onx99 10 месяцев назад

    So the library is discriminating against the stupid..... Not sure how i feel about this 😅

  • @edvinwester8064
    @edvinwester8064 10 месяцев назад

    I can remember:
    3.141592653589793238

  • @lazy_biscuits08
    @lazy_biscuits08 11 месяцев назад

    I had a math exam today so lemme guess before watching:
    First open the brackets to break the integral into two parts.
    The first part can be solved by replacing x with pi-x.
    The second integral is solved with the formula sqrt(a² - x²)

  • @trapperjohn7571
    @trapperjohn7571 11 месяцев назад +2

    Me, being a hacker, got all the information I need to brute-force a captured WPA handshake from "first digits of the answer"

    • @irxosm1
      @irxosm1 10 месяцев назад

      cringe ngl

  • @teelkenjr6325
    @teelkenjr6325 10 месяцев назад

    What is are the integers of pi ? Proceeds to sum up pi in Chinees

  • @blacknoir2404
    @blacknoir2404 11 месяцев назад

    but you can do integrals on a calculator 😂

  • @shaqshock
    @shaqshock 11 месяцев назад

    Pi!!!