An Interesting Nonstandard Equation

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  • Опубліковано 31 жов 2024

КОМЕНТАРІ • 27

  • @fahrenheit2101
    @fahrenheit2101 2 дні тому +14

    Trivial in the reals, x = y, as x + e^x is a monotone, and thus invertible function.

  • @seanfraser3125
    @seanfraser3125 2 дні тому +8

    Take the derivative of x+e^x and get 1+e^x > 0 for all x. So this function is strictly increasing and thus one-to-one.
    So y=x is the only set of solutions.

    • @dan-florinchereches4892
      @dan-florinchereches4892 2 дні тому +3

      This. Notice X and e^x are strictly increasing functions thus the function is bijective so an inverse exists and applying the inverse function x=y

  • @hybmnzz2658
    @hybmnzz2658 День тому

    Rearrange to get -1 = e^x - e^y / x-y which geometrically represents the slope of a secant line for the curve e^z. But it can never be negative.

  • @mohammadkhaksar-t6p
    @mohammadkhaksar-t6p 2 дні тому +3

    f-1(x)= x-e^(x-w(e^x))

    • @stephenshefsky5201
      @stephenshefsky5201 2 дні тому

      Yes, I think that solution works. I obtained f^-1(x) = ln(W(e^x)) from f(x) = x + e^x by using the substitution x = ln(g), then solving for g.

    • @stephenshefsky5201
      @stephenshefsky5201 2 дні тому

      The solution can also take the form f^-1(x) = x - W(e^x).

  • @mtaur4113
    @mtaur4113 2 дні тому

    Skipped forward, saw that approach #2 was what I had in mind and wanted to check that I didn't miss anything. Sometimes we aren't that lucky with functions. 😂

  • @bat3146
    @bat3146 2 дні тому +2

    It wasn't the main point of this video, but 0^0 is false. a^b * a^0 = a^b is true, but you can't divide both side by a^b, if a = 0.

  • @ianfowler9340
    @ianfowler9340 День тому

    I don't think that lim( x^x) _ as x--> 0 being 1 necessarily implies that 0^0 =1.

  • @JefiKnight
    @JefiKnight 2 дні тому

    I was looking for a twist ending...

  • @scottleung9587
    @scottleung9587 2 дні тому +2

    It should be pretty obvious that y=x.

    • @plokoon2301
      @plokoon2301 2 дні тому +1

      It is less obvious that it might not be the general solution.

    • @fahrenheit2101
      @fahrenheit2101 2 дні тому +1

      This does not apply in the general case. y=x is a trivial set of solutions, but not always the only such solution set.
      Indeed, in the complex numbers, there are other less trivial solutions.

  • @imefe.
    @imefe. 2 дні тому +2

    x=y ☝️🤓

  • @Mephisto707
    @Mephisto707 День тому

    F(x) = x + e^x is injective. So, the only solution is y=x.

  • @holyshit922
    @holyshit922 2 дні тому

    Obvious solution y=x

  • @trojanleo123
    @trojanleo123 2 дні тому

    y = x

  • @MathsArena2011
    @MathsArena2011 2 дні тому

    Y can be 1 and e can be 2 and x can be 1

    • @reminderIknows
      @reminderIknows 2 дні тому

      actually, e is a mathematical constant approximately equal to 2.718281828459045 and is equal to 1/0! + 1/1! + 1/2! + 1/3! + ...

  • @trojanleo123
    @trojanleo123 2 дні тому

    f-¹(x) = ln(W[e^x])

  • @Quest3669
    @Quest3669 2 дні тому

    X== y= any. No.

  • @vladimirkaplun5774
    @vladimirkaplun5774 2 дні тому +1

    ?????????

  • @MrMatteuccio82
    @MrMatteuccio82 2 дні тому

    9 minutes for this crap?