Well, you might consider my remark to be really silly . I was thinking about subtraction of reals and the following ideas came to my mind:(adsbygoogle = window.adsbygoogle || []).push({});

From one side, we may consider subtraction to be addition of the inverse of an element, for example:

(5 - 3) - 2 = (5 + (-3)) + (-2).

This "version" of subtraction is associative and (5 + (-3)) + (-2) = 5 + ((-3) + (-2)).

On the other side, if we treat subtraction separately from the addition, it is not associative:

(5 - 3) - 2 is different from 5 - (3 - 2).

Kocur.

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# Confusing subtraction

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