Hi!

My previous/alt account is yetAnotherUser@feddit.de which will be abandoned soon.

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Joined 6 months ago
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Cake day: June 1st, 2024

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  • Ragebait never fails to work.

    How many replies, likes and retweets does the average CNN Twitter post have? I bet this one has more.

    Also this screenshot is from 2019 and the crux of the article is:

    The robots used in the study are clearly robots but have human-like limbs and a head, with exterior complexions that are white – which is to say, pinkish – or black – really, a deep brown.



  • Yes, but similar flaws exist for your proof.

    The algebraic proof that 0.999... = 1 must first prove why you can assign 0.999... to x.

    My "proof" abuses algebraic notation like this - you cannot assign infinity to a variable. After that, regular algebraic rules become meaningless.

    The proper proof would use the definition that the value of a limit approaching another value is exactly that value. For any epsilon > 0, 0.999.. will be within the epsilon environment of 1 (= the interval 1 ± epsilon), therefore 0.999... is 1.


  • Unfortunately not an ideal proof.

    It makes certain assumptions:

    1. That a number 0.999... exists and is well-defined
    2. That multiplication and subtraction for this number work as expected

    Similarly, I could prove that the number which consists of infinite 9's to the left of the decimal separator is equal to -1:

    ...999.0 = x
    ...990.0 = 10x
    
    Calculate x - 10x:
    
    x - 10x = ...999.0 - ...990.0
    -9x = 9
    x = -1
    

    And while this is true for 10-adic numbers, it is certainly not true for the real numbers.