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The $2's$ complement representation of the decimal value $-15$ is

  1. $1111$
  2. $11111$
  3. $111111$
  4. $10001$
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5 Answers

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Best answer
D) is the correct ans.In 2's complement representation, positive numbers are represented in simple binary form and negative numbers are represented in its 2's complement form. So, for -15, we have to complement its binary value - 01111 and add a 1 to it, which gives 10001. Option D.
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Convert the magnitude, -15 to binary.

1111

To make it 8 bits pad 4 extra bits to 1111 (Always Before)

00001111

Negate the number by inverting the bits and adding 1.In simple words 

Take the 2's complement of the no

11110001 (from LSB when u see ist 1 leave it as it is and thereafter flip the all bits.)

To match the answer  ignore most significant 3 bits ANS - 10001

1 comment

actually 5 bits required to represent -15 in 2's compement

because range of 2's complement no is -2n-1 to +2n-1-1

2
0 votes
steps:-

1.compliment of the bits  (0000)

2.add one to the result  (0001)

the answer is front of you  (10001)
0 votes

For -15, we have to complement its binary value - 01111..

actually 5 bits required to represent -15 in 2's compement

because range of 2's complement no is -2n-1 to +2n-1-1 .. therefore it will be 10001

In 2's complement representation positive integers are represented in its normal binary form while negative numbers are represented in its 2's complement form.

0 votes

since the given value is negative, the MSB gets a negative weight

​​​​​​​

$\therefore option~ \large D $

Answer:

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