Question

A gate with two inputs (A,B) and one output (Y) is implemented using a $4\times 1$ MUX as shown in the figure below.


Then the funciton ${}^{\prime }{Y}^{\prime }$ is equal to

• A. $A⨁B$
• B. $A+B$
• C. $B$
• D. $A\overline{B}$

Answer 1

The correct option is C $B$

The expression of $Y$ can be written as
$Y=\left(A\right)\overline{A}\overline{B}+\left(B\right)\overline{A}B+\left(B\right)A\overline{B}+\left(A\right)AB$
$=\overline{A}B+AB=B$