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The circuit shown above is of a differential amplifier. You will see that this circuit is a combination of an inverting and a non-inverting amplifier. Run the circuit and see the output is a difference of the inputs.
The main advantage of this circuit is that this circuit can remove the error caused by common mode voltage. What is common mode voltage? These are signals that are common to both inputs of the opamp. Common mode voltages cause a certain error in the output of the opamp: this error is measured as the common mode rejection ratio. For example, suppose equal 60Hz noise* is present on each input and one input is at 5Vdc and the other is at 2Vdc. The common noise is cancelled out in the difference and the 3V difference is amplified.
This circuit has some restrictions also—it being that the input impedance is limited by the resistors R2 and R3. We all know that the input impedance looking into the amplifier should be high. So if a high gain is required, then a high R0/R2 ratio is required, yet practical circuit considerations limit the maximum and minimum values for these resistors.