1. The problem statement, all variables and given/known data http://img96.imageshack.us/img96/6994/iamge2.png [Broken]http://g.imageshack.us/img96/iamge2.png/1/ [Broken] http://img42.imageshack.us/img42/82/imagevrd.png [Broken]http://g.imageshack.us/img42/imagevrd.png/1/ [Broken] 2. Relevant equations 3. The attempt at a solution I'm following along an example problem in Sedra/Smith and I seem to have gotten stuck. I can see that v_0 = v_i + v_c. For the pictured circuit and input signal I think that v_c = -4V because it seems to me that current will only flow during the 4 volt pulse and since v_c is defined as it is, v_c = -4V. Now, to get v_0 I would think that I would just say v_0 = -4 V + -6 V = -10 V. Unfortunately, the book says the answer is -5 volts. Does anyone see what I've done wrong? Even if I draw it I would think that all of the >0 voltage would be shifted downward so that the most negative number is -10V. Doesn't this circuit ideally shift everything to a negative voltage?