🔍 Key Concepts
• Identify each logic gate in figure 2 (AND, OR, inverter, and which ones are inverted outputs with a bubble).
• Remember the basic truth tables for AND, OR, NAND, and NOR when both inputs are 0.
• Track how the signal flows from A and B through C, D, then through the inverter to E, and finally into the last gate that produces F.
💭 Think About
• When both A and B are 0, what is the output of the upper gate before and after the bubble on its output? Label that as C.
• For the lower gate fed by A and B, what does the output bubble do to the normal OR result, and how does that value change again after passing through the separate inverter to become E?
• Once you know C and E, what kind of gate is the final one, and what output F does it give for those two inputs?
✅ Before You Answer
• Be sure you recognize that a small bubble on a gate’s output means logical inversion (NOT) of that gate’s normal output.
• Verify each intermediate value step-by-step: first find C and D from A and B, then find E from D, and only then compute F from C and E.
• Double-check that you are using the correct truth table for each gate type (AND vs OR, NAND vs NOR) when both inputs are 0.