MAYBE
Time: 0.867

Problem:
 Equations:
  plusAC(plusAC(x3,x4),x5) -> plusAC(x3,plusAC(x4,x5))
  plusAC(x3,x4) -> plusAC(x4,x3)
  timesAC(timesAC(x3,x4),x5) -> timesAC(x3,timesAC(x4,x5))
  timesAC(x3,x4) -> timesAC(x4,x3)
  plusAC(x3,plusAC(x4,x5)) -> plusAC(plusAC(x3,x4),x5)
  plusAC(x4,x3) -> plusAC(x3,x4)
  timesAC(x3,timesAC(x4,x5)) -> timesAC(timesAC(x3,x4),x5)
  timesAC(x4,x3) -> timesAC(x3,x4)
 TRS:
  plusAC(x,0()) -> x
  plusAC(x,i(x)) -> 0()
  i(0()) -> 0()
  i(i(x)) -> x
  i(plusAC(x,y)) -> plusAC(i(x),i(y))
  timesAC(x,1()) -> x
  timesAC(x,0()) -> 0()
  timesAC(x,i(y)) -> i(timesAC(x,y))
  timesAC(x,plusAC(y,z)) -> plusAC(timesAC(x,y),timesAC(x,z))

Proof:
 Open