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by duncangh 31 days ago
This and not being able to divide by 0 in math always drove me up the wall in school. Encountering a god level difficulty unsolved problem in the first 5 minutes of discussion around the basics of the field and then shrugging and continuing to build castles of complexity atop the seemingly rickety foundation irrationally irked me.

Feels good to get that off my Chest. I’ve been holding it in for ~20 years
1 comments
butlike 29 days ago
OK this one still trips me up. Why isn't 5/0 5? If I have 5 apples, and I divide that group by 0, I STILL HAVE 5 APPLES. If I have 5 apples, and I divide that group by 2, I have 2 groups of 2.5 apples.
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t0mpr1c3 28 days ago
Because 0 is not 1.

Consider the equation x = 5/y. Let us assume that the variable x is defined for every value of y. Then x * y = 5 (after multiplying both sides by y).

Let us also assume, as you suggest, that when y = 0, x = 5/0 = 5.

Then x = 5 = x * y. The only solution to this equation is y = 1, a contradiction.

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