Question

Perform binary subtraction using 2's
complement.
8-5​

Answer 1

2's complement binary subtraction:

8-5= ?

Convert into binary form

8= 1000

5= 0101

1000-0101 = 0011

Explanation:

Here A = 1000, B = 0101.

A - B = ?

First find 2's complement of B = 0101

Note : 2's complement of a number is 1 added to it's 1's complement number.

1's complement of 0101 is

1 1 1 1

- 0 1 0 1

_________

1 0 1 0

Now add 1 : 1010 + 1 = 1011

Now Add this 2's complement of B to A

1

1 0 0 0

+ 1 0 1 1

_______

1 0 0 1 1

The left most bit of the result is called carry and it is ignored.

So answer is 0011