- #1
skywolf
- 81
- 0
why can't a computer subtract, or can it, and its just easier to do it by adding?
Computer Subtraction: Can Computers Subtract?
- Thread starter skywolf
- Start date
-
- Tags
- Computer
Click For Summary
Computers can perform subtraction by using addition through the method of 2's complement, which simplifies the circuitry needed for calculations. Mathematically, subtraction can be expressed as addition of a negative, making the operations fundamentally similar. This approach allows computers to handle both signed and unsigned numbers efficiently. While subtraction in binary is not inherently more complex than addition, the use of complements streamlines the process. The same principle applies to decimal numbers, although it is less straightforward than in binary.
- #2
jbusc
- 210
- 0
Thanks to 2's complement, computers actually do subtraction by doing addition. See http://en.wikipedia.org/wiki/2's_complement
- #3
sci-3d
- 6
- 0
In the mathematical point of view, adding or subtracting are the same operation, i.e,
A - B = A + (-B)
That is a reason why computer science concern about signed and unsigned numbers.
A - B = A + (-B)
That is a reason why computer science concern about signed and unsigned numbers.
- #4
Kenneth Mann
- 424
- 3
Its not that it is any more difficult to subtract in binary than to add --- just simply the fact that we don't need to build two sets of circuits, when one set can do both functions by simply using complement operation. By the way, the same can be done with decimal numbers, its just not quite as easy as with binary.
KM
KM