MAYBE
(ignored inputs)COMMENT doi:10.1017/CBO9781139172752 [4] Exercise 6.5 ( a ) submitted by: Takahito Aoto , Junichi Yoshida , and Yoshihito Toyama
Rewrite Rules:
   [ f(g(f(?x))) -> ?x,
     f(g(?x)) -> g(f(?x)) ]
Apply Direct Methods...
Inner CPs:
   [ f(g(g(f(?x_1)))) = g(?x_1),
     f(g(?x)) = g(f(?x)) ]
Outer CPs:
   [ ?x = g(f(f(?x))) ]
Linear
(inner) Parallel CPs: (not computed)
unknown Toyama (Parallel CPs)
Direct Methods: Can't judge

Combined result: Can't judge
10.trs: Failure(unknown CR)
(0 msec.)