I saw this circuit and I want to find the relation between Vin and Vout.
Assuming ideal Op-Amps, If VB>0 then the diode will be ON and A2 acts as a buffer so VB must be equal to the voltage of Virtual short circuit of A1 and then VB=0.
If VB<0 then the transistor and diode will be OFF and there is no way from Vin to VB.
If VB=0 there will be no relation between Vin and Vout and I think this can't be the answer.
What is the true method of analyzing this circuit? (I can find the relation of VB and Vout. my problem is in finding the relation of Vin and VB)