🔍 Key Concepts

• 741 op-amp pin functions shown in figure "C" (which pins are the actual signal inputs vs. trim/offset pins) • Role of a differential amplifier inside an operational amplifier block diagram (figure "A") • Difference between signal inputs and offset null connections on a 741

💭 Think About

• From figure "C", identify which pins are labeled as the inverting and non‑inverting inputs, then match those to the inputs feeding the differential amplifier in figure "A" • Ask yourself: does the differential amplifier need the offset‑null pins, or only the true signal input pins, to sense a voltage difference? • Which pair of pins, when their voltages differ, will cause the op‑amp output to change in normal operation?

✅ Before You Answer

• Verify in figure "C" which pins are explicitly labeled Inverting Input and Non‑Inverting Input • Confirm in figure "A" that the differential amplifier block is driven only by the inverting and non‑inverting inputs (not the power or offset‑null pins) • Eliminate any answer choices that include a pin whose label in figure "C" is not a signal input (e.g., marked as offset null, power, or not connected)