(a) Obtain relationships between vO and vI for the circuit of Fig. P1.20 if R2 5 R1 and VP 5 0. Hint: consider the cases vI . 0 and vI , 0 separately. (b) Repeat, if R2 5 2R1. (c) Repeat if R2 5 4R1...

(a) Obtain relationships between vO and vI for the circuit of Fig. P1.20 if R2 5 R1 and VP 5 0. Hint: consider the cases vI . 0 and vI , 0 separately. (b) Repeat, if R2 5 2R1. (c) Repeat if R2 5 4R1 and both diodes are reversed, so they point toward the left.