CBSE Class 12 · 2008 · All India · SemiconductorsShort Answer

Read the two input waveforms interval by interval and apply each gate's rule.
(i) AND, $Y=A\cdot B$: output is high only in intervals where A and B are simultaneously high.
(ii) NOR, $Y=\overline{A+B}$: output is high only in intervals where both A and B are low.
(iii) NAND, $Y=\overline{A\cdot B}$: output is low only where both are high, and high in all other intervals.
$\boxed{\text{Apply }A\cdot B,\overline{A+B},\overline{A\cdot B}\text{ interval by interval.}}$