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I think a big issue with how we teach math, is the casualness with which we introduce children to floating points.

Its like: Hey little Bobby, now that you can count here are the ints and multiplication/division. For the rest of your life there will be things to learn about them and their algebra.

Tomorrow we'll learn how to put a ".25" behind it. Nothing serious. Just adds multiple different types of infinities with profound impact on exactness and computability, which you have yet to learn about. But it lets you write 1/4 without a fraction which means its simple!



Totally agree. It bothered me when I was younger, though I had no idea how to explain why, but this should be deeply unsettling to everyone who encounters it:

    1/4 = 0.25      exact
    1/3 = 0.333...  infinitely repeating approximation


    1/1  a
    1/2  ah
    1/3  aH!
    1/4  ahh
    1/5  ah
    1/6  ahH!
    1/7  aHHHHHH!
    1/8  ahhh
    1/9  aH!
    1/10 ah
    1/11 aHH!
    1/12 ahhH!
    1/13 aHHHHHH!
    1/14 ahHHHHHH!
    1/15 ahH!
    1/16 ahhhh
    1/17 aHHHHHHHHHHHHHHHH!
    1/18 ahH!
    1/19 aHHHHHHHHHHHHHHHHHH!
    1/20 ahh
https://en.wikipedia.org/wiki/Repeating_decimal#Table_of_val...


Oh that number? It’s just a Laurent series. Just take the limit of the partial sums.


> For the rest of your life there will be things to learn about them and their algebra.

That’s just not true for the vast majority of people.


It's available to learn whether or not they take advantage of it.


Sure. Just like open heart surgery, Medieval English, and penguin husbandry.


There is no floating point here.




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