• Allero@lemmy.today
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    6 months ago

    Why do we even use natural numbers as a subset?

    There are whole numbers already

    • NoFood4u@sopuli.xyz
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      6 months ago

      I’m not too good at math but i think it’s because the set of integers is defined as the set that contains all natural numbers and their opposites, while the set of natural numbers is defined using the successor function - 0 (or 1) is a natural number; if a number n natural, then S(n) is natural where S(n) = n+1.

      • Allero@lemmy.today
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        6 months ago

        Thanks!

        But if we talk whole numbers, we just change the rule that if n is whole, then S(n) is whole where S(n)=n±1.

        Essentially just adding possibility for minus again.