Arithmetic Course/Number Operation/Subtraction

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Subtraction[edit]

Subtraction is an operation where one number is deducted from another. It can be represented by

A - B

Operation[edit]

a - b = -b + a
a - b - c = a - (b + c) = (a - b) - c

Rules[edit]

Any number subtract zero is equal to the number

a - 0 = a

Any number subtract to itself equals zero

a - a = 0

Any number subtract its negative is doubled

a - (-a) = 2a