MAYBE Input TRS: 1: f(a()) -> g(h(a(),b())) 2: g(g(a())) -> f(b()) 3: h(x,x) -> g(a()) Infeasibility test: G(h(a(),b())) --> G(g(a())) Co-Order(NegReal,≥,Sum) ...Co-QLPOpS ...Co-QWPOpS(PosReal,>,Sum) ...Co-Order(PosReal,≥,Sum-Sum; PosReal,≥,Sum-Sum) ...failed.