We can find the output of given combination of gates using Boolean algebra. Consider the given figure
The output Y=A⋅B which is the expression for NAND gate. Alternate method We can find the output of given combination of gates using truth table. Consider the given figure
A
B
Y1=A⋅B
Y=A⋅B
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
0
The above truth table shows the output of NAND gate.