I got this wrong on my quiz, can someone show me how to do this?
With the switch closed a long time the initial current in the inductor is Is+Vs/R1. The voltage across the inductor and the cap is 0. When the switch opens you have 2 independent problems. The voltage source and 2 resistor can be replaced by the Thevenin equivalent which is a voltage of Vs*R2/(R1+R2) and a resistance of RthR1*R2/(R1+R2). Now this is a simple RL circuit with an initial condition. The second circuit is a simple RC circuit.
