MAYBE
Time: 1.370

Problem:
 Equations:
  plusAC(plusAC(x2,x3),x4) -> plusAC(x2,plusAC(x3,x4))
  plusAC(x2,x3) -> plusAC(x3,x2)
  timesAC(timesAC(x2,x3),x4) -> timesAC(x2,timesAC(x3,x4))
  timesAC(x2,x3) -> timesAC(x3,x2)
  plusAC(x2,plusAC(x3,x4)) -> plusAC(plusAC(x2,x3),x4)
  plusAC(x3,x2) -> plusAC(x2,x3)
  timesAC(x2,timesAC(x3,x4)) -> timesAC(timesAC(x2,x3),x4)
  timesAC(x3,x2) -> timesAC(x2,x3)
 TRS:
  p(s(x)) -> x
  plusAC(x,0()) -> x
  plusAC(x,s(y)) -> s(plusAC(x,y))
  timesAC(x,0()) -> 0()
  timesAC(x,s(y)) -> plusAC(x,timesAC(x,y))
  minus(x,0()) -> x
  minus(s(x),s(y)) -> minus(p(s(x)),p(s(y)))
  div(0(),s(y)) -> 0()
  div(s(x),s(y)) -> s(div(minus(x,y),s(y)))

Proof:
 Open