1. The problem statement, all variables and given/known data This problem is to find the I and V by ideal diode model method (assume there is no voltage drop and resistance within the diode) 2. Relevant equations Just simple Ohm's Law equation 3. The attempt at a solution First i assume the diode 2 is open, but i don't know how to calculate the equivalent resistance of the circuit? is that just all in series or R4+R2//R3+R1?