UGC NET CSE | December 2004 | Part 2 | Question: 6

Question

An example of a binary number which is equal to its $2$’s complement is :

• A. $1100$
• B. $1001$
• C. $1000$
• D. $1111$

Answer 1

$2^{'}s$ complement of $1000  =\overline{1000}+1=0111+1=1000$

$(C)$ is the correct option.

Answer 2

2's compliment of 1100=1+1's compliment of 1100=0001+0100=0101

2's compliment of 1001=1+1's compliment of 1001=0001+0110=0111

2's compliment of 1000=1+1's compliment of 1000=0001+0111=1000

2's compliment of 1111=1+1's compliment of 1111=0001+0001=0001

so option c is right answer