COMPUTER SCIENCE AND ENGINEERING
DIGITAL LOGIC
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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P XOR Q
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P OR (NOT Q)
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P AND Q
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P AND (NOT Q)
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Detailed explanation-1: -Operation of Half Subtractor The output borrow of b is zero (0) as long as the minuend bit (A) is greater than or equal to the subtrahend bit (B), i.e. A ≥ B. The output borrow is a 1 when A = 0 and B = 1.
Detailed explanation-2: -The half subtractor is also a building block for subtracting two binary numbers. It has two inputs and two outputs. This circuit is used to subtract two single bit binary numbers A and B. The ‘diff’ and ‘borrow’ are two output states of the half subtractor.
Detailed explanation-3: -Let the input of a subtractor is A and B then what the output will be if A = B? Explanation: The output for A = B will be 0. If A = B, it means that A = B = 0 or A = B = 1. In both of the situation subtractor gives 0 as the output.
Detailed explanation-4: -Like “carry” in addition, to “borrow” in subtraction means to take amounts from one number and assign them to the next. In this procedure, the 10 is borrowed from the next higher digit column in order to obtain a positive difference in the nearby column.