• 21 Expansion of Numbers and Operations
ᐥoperators + − ×(·) / ˄ ˅ ⍻
numbers ℕ ℤ ℚ ℝᐥ
The whole numbers are closed under addition.
Subtraction is the inverse operation of addition.
l + m = n
n - m = l
Define negative integers then integers are closed under subtraction.
Multiplication is repea ...
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