GATE IT 2004 | Question: 8

Question

What is the minimum number of $\text{NAND}$ gates required to implement a $2\text{-input EXCLUSIVE-OR}$ function without using any other logic gate?

• A. $2$
• B. $4$
• C. $5$
• D. $6$

Comments

How A'+AB= A'+B

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@smartmeet as you know that               A+BC = (A+B)(A+C). So.                        A^+AB=(A^+A)(A^+B)   //A^+A=1.              So we can say A^+AB =A^+B

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@bikram sir

make edit in option B.

Answer 1

$\begin{array}{|c | c | c|} \hline \textbf{GATE} & \textbf{NAND} & \textbf{NOR} \\ \hline \text{NOT} & 1 & 1 \\ \hline \text{AND} & 2 & 3 \\ \hline \text{OR} & 3 & 2 \\ \hline \text{NAND} & 1 & 4 \\ \hline \text{NOR} & 4 & 1 \\ \hline \text{EX-OR} & 4 & 5 \\ \hline \text{EX-NOR} & 5 & 4 \\ \hline \text{HALF ADDER} & 5 & 5 \\ \hline \text{FULL ADDER} & 9 & 9 \\ \hline \end{array}$