Level:
Lib
Thy
Top
:
Hypotheses:
None
Conclusion:
M,N:Formula List.
(M @ N) =
M +
N
Applied Tactic:
D 0 THENA Auto
Generated subgoals:
1
.
N:Formula List.
(M @ N) =
M +
N
M,N:Formula List. 
(M @ N) = M + NN:Formula List. (M @ N) = M + N