MAYBE
0.09/0.18	MAYBE
0.09/0.18	
0.09/0.18	Problem:
0.09/0.18	 din(der(plus(X,Y))) -> u21(din(der(X)),X,Y)
0.09/0.18	 u21(dout(DX),X,Y) -> u22(din(der(Y)),X,Y,DX)
0.09/0.18	 u22(dout(DY),X,Y,DX) -> dout(plus(DX,DY))
0.09/0.18	 din(der(times(X,Y))) -> u31(din(der(X)),X,Y)
0.09/0.18	 u31(dout(DX),X,Y) -> u32(din(der(Y)),X,Y,DX)
0.09/0.18	 u32(dout(DY),X,Y,DX) -> dout(plus(times(X,DY),times(Y,DX)))
0.09/0.18	 din(der(der(X))) -> u41(din(der(X)),X)
0.09/0.18	 u41(dout(DX),X) -> u42(din(der(DX)),X,DX)
0.09/0.18	 u42(dout(DDX),X,DX) -> dout(DDX)
0.09/0.18	
0.09/0.18	Proof:
0.09/0.18	 Open
0.09/0.18	EOF