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Subtraction

Subtraction is the operation of taking the difference d=x-y of two numbers x and y. Here, x is called the minuend, y is called the subtrahend, and the symbol between the x and y is called the minus sign. The expression "x-y" is read "x minus y."

Subtraction is the inverse of addition, so x+y-y=x-y+y=x.

The subtraction of a number from itself gives 0, while the subtraction of a real number from a smaller real number gives a negative real number. Subtraction of real numbers can be naturally extended to complex numbers.

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