please use L'Hospital's Rule for the limit of x^sqrt(x) as x goes to 0+

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  • čas pƙidĂĄn 20. 08. 2024
  • We will use L'Hospital's Rule for the limit of x^sqrt(x) as x goes to 0+. Even though we will get a 0^0 when we plug in 0 into x^sqrt(x), 0^0 IS an indeterminate form so we must do more work in order to determine the limit. Here's an example of the limit with the indeterminate form 0^0 but we do not get 1. 👉 ‱ a 0^0 limit that appro...
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Komentáƙe • 53

  • @catlooks
    @catlooks Pƙed 2 lety +86

    "This is an indeterminable form because it's on my shirt"
    nice proof lol

  • @nerduto1
    @nerduto1 Pƙed 2 lety +14

    How to always be correct in math:
    Use your shirt as proof.

  • @theRipintheChat
    @theRipintheChat Pƙed rokem +3

    I find it hilarious that you have stocked up a shelf full of expo markers like your holding out for the apocalypse.

  • @vaxjoaberg
    @vaxjoaberg Pƙed 2 lety +15

    Poor L'Hopital. Because we think it's funny an entire generation of math enthusiasts are going to grow up believing his name is L'Hospital. And in a generation after that his original name will be lost to time.

    • @ericsills6484
      @ericsills6484 Pƙed 2 lety +1

      He actually made a mistake. There's no 's' in L'Hopital. I guess I can give him a break though. He wasn't around in the 1600's :-)

    • @Goldfrapplol
      @Goldfrapplol Pƙed 2 lety +6

      Well, actually in older French spelling his name was spelled L'Hospital, which is why it's written today in modern French with an o circumflex: L'HĂŽpital.
      Source: Math major currently speaking French at A1 level so I can understand fundamental math treatises. 😀

    • @ericsills6484
      @ericsills6484 Pƙed 2 lety

      @@Goldfrapplol Je suis corrigé.

    • @vaxjoaberg
      @vaxjoaberg Pƙed 2 lety

      @@Goldfrapplol Thanks, that's good to know. I feel less bad for poor L'Ho(s)pital, now.

  • @hassanalihusseini1717
    @hassanalihusseini1717 Pƙed 2 lety +7

    Nice example for the use of Hopital rule! Thank you!

  • @robinson5923
    @robinson5923 Pƙed 2 lety +19

    Is that the Heisenberg uncertainty cat in your shirt?

    • @EE-ho1iz
      @EE-ho1iz Pƙed 2 lety +16

      It's all the indeterminate form, so it's technically an indeterminate cat!
      Wait a dang minute... :O

    • @oenrn
      @oenrn Pƙed 2 lety +9

      You mean Schrödinger?

  • @GirishManjunathMusic
    @GirishManjunathMusic Pƙed 2 lety +9

    Before watching the video:
    Find the lim(x→0+) x↑(x↑œ)
    Consider x↑(x↑œ) as exp((x↑œ)(lnx))
    lim(x→0+) exp((x↑œ)(lnx))
    as exponential function is continuous over the target domain,
    limit of the exponential function of a function of x is the same as the exponential function of the limit of that function of x.
    thus lim(x→0+) exp((x↑œ)(lnx)) = exp(lim(x→0+) ((x↑œ)(lnx)))
    Defining L = lim(x→0+) ((x↑œ)(lnx)):
    The question now reduces to: Find exp(L).
    L = lim(x→0+) ((x↑œ)(lnx))
    This is of the indeterminate form 0·(-∞)
    Rewriting to obtain a more workable indeterminate form,
    L = lim(x→0+) ((lnx)/(x↑(-Âœ))),
    which is of the indeterminate form (-∞)/∞, allowing for the use of L'Hospital's Rule.
    L = lim(x→0+) (d/dx (lnx)/d/dx (x↑(-Âœ))),
    = lim(x→0+) ((x↑(-1)/((-Âœ)(x↑(-3/2))))
    = lim(x→0+) (-2√x) = 0
    L = 0.
    exp(L) = exp(0) = 1.
    Thus, lim(x→0+) x↑(x↑œ) = exp(L) = 1.

    • @GirishManjunathMusic
      @GirishManjunathMusic Pƙed 2 lety +4

      After Watching the Video: hey my solution was essentially the same as the second method you showed!

    • @Rzko
      @Rzko Pƙed 2 lety +1

      Why do americans love this "L'hopitals rule"? Just use the "growth comparison" (that's how it's named in french), α^x is dominant over x^α which is dominant over ln(x), with "α" a constant

    • @tricky778
      @tricky778 Pƙed 2 lety

      Fyi, the up arrow normally denotes the Boolean 'nand' connective

    • @GirishManjunathMusic
      @GirishManjunathMusic Pƙed 2 lety

      @@Rzko this is a series on L'Hospital's Rule in finding limits of certain indeterminate forms.

    • @GirishManjunathMusic
      @GirishManjunathMusic Pƙed 2 lety

      @@tricky778 FYI, as we're working with limits and not Boolean logic, the up arrow denotes exponentiation. a↑b = a multiplied by itself b times.

  • @black_pantheon
    @black_pantheon Pƙed 8 měsĂ­ci

    watching your videos actually inspires me to buy a whiteboard with markers and a eraser to study math lol no joke

  • @channelsixtysix066
    @channelsixtysix066 Pƙed 2 lety +1

    One other important thing to remember, all you mathematicians out there. If it's on the t-shirt, it gotta be right.

  • @pan_nekdo
    @pan_nekdo Pƙed 2 lety +4

    I prefer u=1/x substitution.

    • @leviuchiha3706
      @leviuchiha3706 Pƙed 2 lety

      Doesn't make any difference.. as it becomes lim(u-infinity) (1/u)^(1/u)^1/2
      ... it becomes more complicated....

    • @pan_nekdo
      @pan_nekdo Pƙed 2 lety

      @@leviuchiha3706 After taking logaritm it's the L'H use obvious.

  • @DaltonPritt
    @DaltonPritt Pƙed 4 měsĂ­ci

    Thank you!

  • @mutenfuyael3461
    @mutenfuyael3461 Pƙed 2 lety +3

    If you know that xln(x) when x approches 0 is 0, you can write sqrt (x) * ln(x) as 2(sqrt(x)*ln(sqrt (x))= 2*0=0=L because sqrt (x) approches 0 when x approches 0, so do it sqrt (x)*ln(sqrt(x))

  • @smitad7881
    @smitad7881 Pƙed rokem +1

    Thanks. Prefer 1st method.

  • @chickenadobo9966
    @chickenadobo9966 Pƙed 11 dny

    natatawa talaga ako pag nagssigh siya HAHAHHAHA (filipino here struggling sa engineering)

  • @domc3743
    @domc3743 Pƙed 2 lety +1

    Let x= y^2 then we have y^2y = lim y^y * lim y^y = 1*1 =1

  • @absurdtuber3341
    @absurdtuber3341 Pƙed rokem

    Thank you

  • @space_engineer17
    @space_engineer17 Pƙed 2 lety +6

    0:10
    Why 0^0 is indeterminate?
    Because it's on the shirt!!😂
    Notice that Schrodinger cat
    Indeterminate catđŸ˜±

  • @NXT_LVL_DVL
    @NXT_LVL_DVL Pƙed 2 lety +3

    You did the same method two times actually

  • @saveerjain6833
    @saveerjain6833 Pƙed 2 lety

    1:12 Sorry what word did you use for the type of function that natural log is?

    • @ZipplyZane
      @ZipplyZane Pƙed 2 lety

      Ln is a *continuous* function.

    • @saveerjain6833
      @saveerjain6833 Pƙed 2 lety

      @@ZipplyZane thank you!

    • @ZipplyZane
      @ZipplyZane Pƙed 2 lety +1

      @@saveerjain6833 To be clear, it only works because ln is continuous in the relevant interval, which is near 0 on the positive side.

    • @saveerjain6833
      @saveerjain6833 Pƙed 2 lety

      @@ZipplyZane no yeha i get that just didn’t hear the word

  • @matteocilla9482
    @matteocilla9482 Pƙed 2 lety

    hello, i forget the conditions to use L’H ?? can you remind me pls ??

    • @tricky778
      @tricky778 Pƙed 2 lety

      1 requirement is that the numerator and denominator either both approach zero or both approach infinite size

    • @tricky778
      @tricky778 Pƙed 2 lety

      Another is that both are differentiable in the relevant region

  • @Measure_differentiable
    @Measure_differentiable Pƙed 2 měsĂ­ci

    This is wrong. YOU CANT USE L'HOPITALS RULE HERE. MOREOVER YOU DO NOT NEED TO .

  • @AKeenCabinTV
    @AKeenCabinTV Pƙed 2 lety

    This was just recommended to me but wtf is this...