14.17 You are given two circuits as shown in Fig. 14.46, which consist of NAND gates. Identify the logic operation carried out by the two circuits.

(a) Hint: Identify the truth table for a given circuit.
Step: Find the output for the given circuit.The output of the left NAND gate will be, as shown in the following figure.

Hence, the output of the combination of the two NAND gates is given as:

Hence, this circuit functions as an AND gate.

(b)Hint: Identify the truth table for a given circuit.
Step: Find the output for the given circuit.
is the output of the upper left of the NAND gate and is the output of the lower half of the NAND gate, as shown in the following figure.

Hence, the output of the combination of the NAND gates will be given as:

Hence, this circuit functions as an OR gate.