Please see the attached file for diagram.
Determine Vc(t) for t>0. The voltage across the capacitor in figure just before the switch is changed is given below: Vc(0) = -7V
Io = 12mA
C = 0.55muF
R1 = 7kOhms
R2 = 3.3 kOhms
This a very tricky question.
First remember that we deal with an ideal current source. If we have a closed loop then the current must be 12mA, no more no ...
The solution talks through the voltage problem conceptually, following a train of thought from beginning to the end conclusion and trying to anticipate and answer questions the reader might have along the way.