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Q.
Output $ Y $ is given by:
Bihar CECEBihar CECE 2007Semiconductor Electronics: Materials Devices and Simple Circuits
Solution:
We can realise the combination as shown below.
Gate-$1 $ is OR gate while gate-$2$ is AND gate.
Output of OR gate, $W_{1}=\bar{X}+\bar{Y}$
Thus, output of AND gate,
$W =W_{1} \cdot Z $
$=(\vec{X}+\bar{Y}) \cdot Z$