An OPAMP with input offset voltage

[fgda]

1. The problem statement, all variables and given/known data

2. Relevant equations

Superposition

Non-inverting OPAMP: V_out = (1 + R/R)V_in = 2*V_in2

Inverting OPAMP: V_out = -V_in

V_os = 2.5mV

3. The attempt at a solution

1. V_in enabled, V_os disabled

V_out1 = -V_in

2. V_os enabled, V_in disabled

To get V_out2, use the non inv. equation where V_in2 is equal to V_1 + V_os

where V_1 is the node between R and R at the middle bottom of the circuit.

V_out2 = 2*(V_1 + V_os)

3. V_out = V_out1 + V_out2

Is this the correct approach?

Thanks in advance

I'm pretty sure that step 2 is correct. The professor did an example in class that was similar enough to that case. But in step 1, I have input voltage at both OPAMP terminals so I do not know what to do. I'd rather take the OPAMP as a black box with a characteristic equation if possible.