Final answer:
The input voltage range to keep an op amp in its linear operating region is typically between the positive and negative power supply voltages minus a couple of volts. The exact range varies for different op amps and should be checked in the datasheet for accurate values.
Step-by-step explanation:
The range of input voltages that will keep the operational amplifier (op amp) in its linear operating region is typically between the positive and negative power supply voltages minus a couple of volts. For an op amp to remain in the linear region, the output must not reach the saturation levels, which occur near the supply voltages. Most op amps are designed to operate with dual power supplies; therefore, the linear operating range might be, for instance, from +12V to -12V, but the actual linear range would be something like +10V to -10V. It is important to consult the specific datasheet of the op amp in question for precise values, as these can vary significantly based on the design and technology of the op amp.