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What Mike said is true. I am providing more information for those who want to dig a little deeper. Write down the equation which provides the value of Vo, the output of the op-amp, as a function of Vin. Start with Vin = 1 Volt to make it easy.

In a perfect world, the input impedances of an op-amp are infinite. The output impedance of the op-amp is zero. Same is true of the voltage source Vin. Also, the differential voltage between + and - inputs to the op-amp is zero. Furthermore, the open loop gain of an op-amp is infinite. In the real world, none of this is true. The bias currents, which are necessary to activate the differential input circuits of the op-amp, are exceedingly small which means that what is said at the beginning are fair assumptions to make to address the present problem. The bias current flowing in the parallel combination of R2 and R3 produces a voltage at the inverting input of the op-amp which can be cancelled at the non-inverting input of the op-amp with the addition of R1 with the value of R2||R3. In other words, the error produced at the output of the op-amp caused by the input offset voltage as a result of the bias currents can be eliminated.

What Mike said is true. I am providing more information for those who want to dig a little deeper. Write down the equation which provides the value of Vo, the output of the op-amp, as a function of Vin. Start with Vin = 1 Volt to make it easy.

In a perfect world, the input impedances of an op-amp are infinite. The output impedance of the op-amp is zero. Same is true of the voltage source Vin. Also, the differential voltage between + and - inputs to the op-amp is zero. Furthermore, the open loop gain of an op-amp is infinite. In the real world, none of this is true. The bias currents, which are necessary to activate the differential input circuits of the op-amp, are exceedingly small which means that what is said at the beginning are fair assumptions to make to address the present problem. The bias current flowing in the parallel combination of R2 and R3 produces a voltage at the inverting input of the op-amp which can be cancelled at the non-inverting input of the op-amp with the addition of R1 with the value of R2||R3. In other words, the error produced at the output of the op-amp caused by the input offset voltage, because of the bias currents, can be eliminated.

In a perfect world, the input impedances of an op-amp are infinite. The output impedance of the op-amp is zero. Same is true of the voltage source Vin. Also, the differential voltage between + and - inputs to the op-amp is zero. Furthermore, the open loop gain of an op-amp is infinite. In the real world, none of this is true. The bias currents, which are necessary to activate the differential input circuits of the op-amp, are exceedingly small which means that what is said at the beginning are fair assumptions to make to address the present problem. The bias current flowing in the parallel combination of R2 and R3 produces a voltage at the inverting input of the op-amp which can be cancelled at the non-inverting input of the op-amp with the addition of R1 with the value of R2||R3. In other words, the error produced at the output of the op-amp caused by the input offset voltage as a result of the bias currents can be eliminated.

What Mike said is true. I am providing more information for those who want to dig a little deeper. Write down the equation which provides the value of Vo, the output of the op-amp, as a function of Vin. Start with Vin = 1 Volt to make it easy.

In a perfect world, the input impedances of an op-amp are infinite. The output impedance of the op-amp is zero. Same is true of the voltage source Vin. Also, the differential voltage between + and - inputs to the op-amp is zero. Furthermore, the open loop gain of an op-amp is infinite. In the real world, none of this is true. The bias currents, which are necessary to activate the differential input circuits of the op-amp, are exceedingly small which means that what is said at the beginning are fair assumptions to make to address the present problem. The bias current flowing in the parallel combination of R2 and R3 produces a voltage at the inverting input of the op-amp which can be cancelled at the non-inverting input of the op-amp with the addition of R1 with the value of R2||R3. In other words, the error produced at the output of the op-amp caused by the input offset voltage as a result of the bias currents can be eliminated.

In an ideal world, the input impedances of an op-amp are infinite. The output impedance of the op-amp is zero. Same is true of the voltage source Vin. Also, the differential voltage between + and - inputs to the op-amp is zero. Furthermore, the open loop gain of an op-amp is infinite. In the real world, none of this is true. The bias currents, which are necessary to activate the differential input circuits of the op-amp, are exceedingly small which means that what is said at the beginning are fair assumptions to make to address the present problem. The bias current flowing in the parallel combination of R2 and R3 produces a voltage at the inverting input of the op-amp which can be cancelled at the non-inverting input of the op-amp with the addition of R1 with the value of R2||R3. In other words, the error produced at the output of the op-amp caused by the input offset voltage as a result of the bias currents can be eliminated.

In a perfect world, the input impedances of an op-amp are infinite. The output impedance of the op-amp is zero. Same is true of the voltage source Vin. Also, the differential voltage between + and - inputs to the op-amp is zero. Furthermore, the open loop gain of an op-amp is infinite. In the real world, none of this is true. The bias currents, which are necessary to activate the differential input circuits of the op-amp, are exceedingly small which means that what is said at the beginning are fair assumptions to make to address the present problem. The bias current flowing in the parallel combination of R2 and R3 produces a voltage at the inverting input of the op-amp which can be cancelled at the non-inverting input of the op-amp with the addition of R1 with the value of R2||R3. In other words, the error produced at the output of the op-amp caused by the input offset voltage as a result of the bias currents can be eliminated.