7.1 The Source-Free
RC Circuit (4)
Example 1
  Refer to the circuit below, determine vC, vx, and
io for t ≥ 0.
  Assume that vC(0) = 30 V.
Please refer to lecture or textbook for more detail elaboration.
Answer: vC = 30e–0.25t V ; vx = 10e–0.25t ; io = –2.5e–0.25t A