0.04/0.13 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.04/0.13 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.15/0.34 % Computer : n024.cluster.edu 0.15/0.34 % Model : x86_64 x86_64 0.15/0.34 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.15/0.34 % Memory : 8042.1875MB 0.15/0.34 % OS : Linux 3.10.0-693.el7.x86_64 0.15/0.34 % CPULimit : 180 0.15/0.34 % DateTime : Thu Aug 29 09:42:20 EDT 2019 0.15/0.34 % CPUTime : 0.21/0.45 % SZS status Unsatisfiable 0.21/0.45 0.21/0.45 % SZS output start Proof 0.21/0.45 Take the following subset of the input axioms: 0.21/0.48 fof(multiply, axiom, ![B, A]: inverse(double_divide(B, A))=multiply(A, B)). 0.21/0.48 fof(prove_these_axioms_3, negated_conjecture, multiply(a3, multiply(b3, c3))!=multiply(multiply(a3, b3), c3)). 0.21/0.48 fof(single_axiom, axiom, ![B, A, C]: double_divide(inverse(double_divide(double_divide(A, B), inverse(double_divide(A, inverse(C))))), B)=C). 0.21/0.48 0.21/0.48 Now clausify the problem and encode Horn clauses using encoding 3 of 0.21/0.48 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 0.21/0.48 We repeatedly replace C & s=t => u=v by the two clauses: 0.21/0.48 fresh(y, y, x1...xn) = u 0.21/0.48 C => fresh(s, t, x1...xn) = v 0.21/0.48 where fresh is a fresh function symbol and x1..xn are the free 0.21/0.48 variables of u and v. 0.21/0.48 A predicate p(X) is encoded as p(X)=true (this is sound, because the 0.21/0.48 input problem has no model of domain size 1). 0.21/0.48 0.21/0.48 The encoding turns the above axioms into the following unit equations and goals: 0.21/0.48 0.21/0.48 Axiom 1 (single_axiom): double_divide(inverse(double_divide(double_divide(X, Y), inverse(double_divide(X, inverse(Z))))), Y) = Z. 0.21/0.49 Axiom 2 (multiply): inverse(double_divide(X, Y)) = multiply(Y, X). 0.21/0.49 0.21/0.49 Lemma 3: multiply(X, multiply(multiply(inverse(Z), Y), double_divide(Y, X))) = inverse(Z). 0.21/0.49 Proof: 0.21/0.49 multiply(X, multiply(multiply(inverse(Z), Y), double_divide(Y, X))) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 multiply(X, multiply(inverse(double_divide(Y, inverse(Z))), double_divide(Y, X))) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 multiply(X, inverse(double_divide(double_divide(Y, X), inverse(double_divide(Y, inverse(Z)))))) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 inverse(double_divide(inverse(double_divide(double_divide(Y, X), inverse(double_divide(Y, inverse(Z))))), X)) 0.21/0.49 = { by axiom 1 (single_axiom) } 0.21/0.49 inverse(Z) 0.21/0.49 0.21/0.49 Lemma 4: double_divide(multiply(multiply(inverse(X), Y), double_divide(Y, Z)), Z) = X. 0.21/0.49 Proof: 0.21/0.49 double_divide(multiply(multiply(inverse(X), Y), double_divide(Y, Z)), Z) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(multiply(inverse(double_divide(Y, inverse(X))), double_divide(Y, Z)), Z) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(inverse(double_divide(double_divide(Y, Z), inverse(double_divide(Y, inverse(X))))), Z) 0.21/0.49 = { by axiom 1 (single_axiom) } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 5: double_divide(multiply(inverse(Y), Y), inverse(X)) = X. 0.21/0.49 Proof: 0.21/0.49 double_divide(multiply(inverse(Y), Y), inverse(X)) 0.21/0.49 = { by lemma 3 } 0.21/0.49 double_divide(multiply(multiply(inverse(X), multiply(multiply(inverse(Y), ?), double_divide(?, inverse(X)))), Y), inverse(X)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(multiply(inverse(double_divide(multiply(multiply(inverse(Y), ?), double_divide(?, inverse(X))), inverse(X))), Y), inverse(X)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(inverse(double_divide(Y, inverse(double_divide(multiply(multiply(inverse(Y), ?), double_divide(?, inverse(X))), inverse(X))))), inverse(X)) 0.21/0.49 = { by lemma 4 } 0.21/0.49 double_divide(inverse(double_divide(double_divide(multiply(multiply(inverse(Y), ?), double_divide(?, inverse(X))), inverse(X)), inverse(double_divide(multiply(multiply(inverse(Y), ?), double_divide(?, inverse(X))), inverse(X))))), inverse(X)) 0.21/0.49 = { by axiom 1 (single_axiom) } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 6: multiply(inverse(X), multiply(inverse(Y), Y)) = inverse(X). 0.21/0.49 Proof: 0.21/0.49 multiply(inverse(X), multiply(inverse(Y), Y)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 inverse(double_divide(multiply(inverse(Y), Y), inverse(X))) 0.21/0.49 = { by lemma 5 } 0.21/0.49 inverse(X) 0.21/0.49 0.21/0.49 Lemma 7: double_divide(multiply(inverse(Z), Z), multiply(Y, X)) = double_divide(X, Y). 0.21/0.49 Proof: 0.21/0.49 double_divide(multiply(inverse(Z), Z), multiply(Y, X)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(multiply(inverse(Z), Z), inverse(double_divide(X, Y))) 0.21/0.49 = { by lemma 5 } 0.21/0.49 double_divide(X, Y) 0.21/0.49 0.21/0.49 Lemma 8: double_divide(multiply(inverse(X), Y), inverse(Y)) = X. 0.21/0.49 Proof: 0.21/0.49 double_divide(multiply(inverse(X), Y), inverse(Y)) 0.21/0.49 = { by lemma 6 } 0.21/0.49 double_divide(multiply(multiply(inverse(X), multiply(inverse(?), ?)), Y), inverse(Y)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(multiply(inverse(double_divide(multiply(inverse(?), ?), inverse(X))), Y), inverse(Y)) 0.21/0.49 = { by axiom 1 (single_axiom) } 0.21/0.49 double_divide(multiply(inverse(double_divide(multiply(inverse(?), ?), inverse(X))), double_divide(inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))), ?)), inverse(Y)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(inverse(double_divide(double_divide(inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))), ?), inverse(double_divide(multiply(inverse(?), ?), inverse(X))))), inverse(Y)) 0.21/0.49 = { by lemma 7 } 0.21/0.49 double_divide(inverse(double_divide(double_divide(multiply(inverse(?), ?), multiply(?, inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))))), inverse(double_divide(multiply(inverse(?), ?), inverse(X))))), inverse(Y)) 0.21/0.49 = { by lemma 3 } 0.21/0.49 double_divide(inverse(double_divide(double_divide(multiply(inverse(?), ?), multiply(?, inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))))), inverse(double_divide(multiply(inverse(?), ?), inverse(X))))), multiply(?, multiply(multiply(inverse(Y), ?), double_divide(?, ?)))) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(inverse(double_divide(double_divide(multiply(inverse(?), ?), multiply(?, inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))))), inverse(double_divide(multiply(inverse(?), ?), inverse(X))))), multiply(?, multiply(inverse(double_divide(?, inverse(Y))), double_divide(?, ?)))) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(inverse(double_divide(double_divide(multiply(inverse(?), ?), multiply(?, inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))))), inverse(double_divide(multiply(inverse(?), ?), inverse(X))))), multiply(?, inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))))) 0.21/0.49 = { by axiom 1 (single_axiom) } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 9: multiply(inverse(X), multiply(inverse(Y), X)) = inverse(Y). 0.21/0.49 Proof: 0.21/0.49 multiply(inverse(X), multiply(inverse(Y), X)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 inverse(double_divide(multiply(inverse(Y), X), inverse(X))) 0.21/0.49 = { by lemma 8 } 0.21/0.49 inverse(Y) 0.21/0.49 0.21/0.49 Lemma 10: multiply(inverse(multiply(inverse(Y), X)), inverse(Y)) = inverse(X). 0.21/0.49 Proof: 0.21/0.49 multiply(inverse(multiply(inverse(Y), X)), inverse(Y)) 0.21/0.49 = { by lemma 9 } 0.21/0.49 multiply(inverse(multiply(inverse(Y), X)), multiply(inverse(X), multiply(inverse(Y), X))) 0.21/0.49 = { by lemma 9 } 0.21/0.49 inverse(X) 0.21/0.49 0.21/0.49 Lemma 11: double_divide(inverse(Y), inverse(multiply(inverse(Y), X))) = X. 0.21/0.49 Proof: 0.21/0.49 double_divide(inverse(Y), inverse(multiply(inverse(Y), X))) 0.21/0.49 = { by lemma 9 } 0.21/0.49 double_divide(multiply(inverse(X), multiply(inverse(Y), X)), inverse(multiply(inverse(Y), X))) 0.21/0.49 = { by lemma 8 } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 12: multiply(inverse(X), X) = multiply(inverse(?), ?). 0.21/0.49 Proof: 0.21/0.49 multiply(inverse(X), X) 0.21/0.49 = { by lemma 11 } 0.21/0.49 double_divide(inverse(Y), inverse(multiply(inverse(Y), multiply(inverse(X), X)))) 0.21/0.49 = { by lemma 6 } 0.21/0.49 double_divide(inverse(Y), inverse(inverse(Y))) 0.21/0.49 = { by lemma 6 } 0.21/0.49 double_divide(inverse(Y), inverse(multiply(inverse(Y), multiply(inverse(?), ?)))) 0.21/0.49 = { by lemma 11 } 0.21/0.49 multiply(inverse(?), ?) 0.21/0.49 0.21/0.49 Lemma 13: double_divide(inverse(X), inverse(multiply(inverse(?), ?))) = X. 0.21/0.49 Proof: 0.21/0.49 double_divide(inverse(X), inverse(multiply(inverse(?), ?))) 0.21/0.49 = { by lemma 6 } 0.21/0.49 double_divide(multiply(inverse(X), multiply(inverse(?), ?)), inverse(multiply(inverse(?), ?))) 0.21/0.49 = { by lemma 8 } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 14: double_divide(Y, multiply(inverse(X), inverse(Y))) = X. 0.21/0.49 Proof: 0.21/0.49 double_divide(Y, multiply(inverse(X), inverse(Y))) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 double_divide(Y, inverse(double_divide(inverse(Y), inverse(X)))) 0.21/0.49 = { by lemma 13 } 0.21/0.49 double_divide(inverse(double_divide(Y, inverse(double_divide(inverse(Y), inverse(X))))), inverse(multiply(inverse(?), ?))) 0.21/0.49 = { by lemma 13 } 0.21/0.49 double_divide(inverse(double_divide(double_divide(inverse(Y), inverse(multiply(inverse(?), ?))), inverse(double_divide(inverse(Y), inverse(X))))), inverse(multiply(inverse(?), ?))) 0.21/0.49 = { by axiom 1 (single_axiom) } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 15: double_divide(X, inverse(Y)) = multiply(inverse(X), Y). 0.21/0.49 Proof: 0.21/0.49 double_divide(X, inverse(Y)) 0.21/0.49 = { by lemma 10 } 0.21/0.49 double_divide(X, multiply(inverse(multiply(inverse(X), Y)), inverse(X))) 0.21/0.49 = { by lemma 14 } 0.21/0.49 multiply(inverse(X), Y) 0.21/0.49 0.21/0.49 Lemma 16: inverse(inverse(X)) = X. 0.21/0.49 Proof: 0.21/0.49 inverse(inverse(X)) 0.21/0.49 = { by lemma 6 } 0.21/0.49 multiply(inverse(inverse(X)), multiply(inverse(?), ?)) 0.21/0.49 = { by lemma 15 } 0.21/0.49 double_divide(inverse(X), inverse(multiply(inverse(?), ?))) 0.21/0.49 = { by lemma 13 } 0.21/0.49 X 0.21/0.49 0.21/0.49 Lemma 17: inverse(multiply(Y, X)) = double_divide(X, Y). 0.21/0.49 Proof: 0.21/0.49 inverse(multiply(Y, X)) 0.21/0.49 = { by axiom 2 (multiply) } 0.21/0.49 inverse(inverse(double_divide(X, Y))) 0.21/0.49 = { by lemma 16 } 0.21/0.50 double_divide(X, Y) 0.21/0.50 0.21/0.50 Lemma 18: multiply(X, Y) = multiply(Y, X). 0.21/0.50 Proof: 0.21/0.50 multiply(X, Y) 0.21/0.50 = { by lemma 16 } 0.21/0.50 multiply(inverse(inverse(X)), Y) 0.21/0.50 = { by lemma 15 } 0.21/0.50 double_divide(inverse(X), inverse(Y)) 0.21/0.50 = { by lemma 8 } 0.21/0.50 double_divide(multiply(inverse(double_divide(inverse(X), inverse(Y))), X), inverse(X)) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(multiply(multiply(inverse(Y), inverse(X)), X), inverse(X)) 0.21/0.50 = { by lemma 15 } 0.21/0.50 multiply(inverse(multiply(multiply(inverse(Y), inverse(X)), X)), X) 0.21/0.50 = { by lemma 17 } 0.21/0.50 multiply(double_divide(X, multiply(inverse(Y), inverse(X))), X) 0.21/0.50 = { by lemma 14 } 0.21/0.50 multiply(Y, X) 0.21/0.50 0.21/0.50 Lemma 19: double_divide(multiply(multiply(multiply(Y, X), Z), double_divide(Z, W)), W) = double_divide(X, Y). 0.21/0.50 Proof: 0.21/0.50 double_divide(multiply(multiply(multiply(Y, X), Z), double_divide(Z, W)), W) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(multiply(inverse(double_divide(Z, multiply(Y, X))), double_divide(Z, W)), W) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(inverse(double_divide(double_divide(Z, W), inverse(double_divide(Z, multiply(Y, X))))), W) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(inverse(double_divide(double_divide(Z, W), inverse(double_divide(Z, inverse(double_divide(X, Y)))))), W) 0.21/0.50 = { by axiom 1 (single_axiom) } 0.21/0.50 double_divide(X, Y) 0.21/0.50 0.21/0.50 Lemma 20: double_divide(X, Y) = double_divide(Y, X). 0.21/0.50 Proof: 0.21/0.50 double_divide(X, Y) 0.21/0.50 = { by lemma 19 } 0.21/0.50 double_divide(multiply(multiply(multiply(Y, X), ?), double_divide(?, ?)), ?) 0.21/0.50 = { by lemma 18 } 0.21/0.50 double_divide(multiply(multiply(multiply(X, Y), ?), double_divide(?, ?)), ?) 0.21/0.50 = { by lemma 19 } 0.21/0.50 double_divide(Y, X) 0.21/0.50 0.21/0.50 Lemma 21: double_divide(multiply(inverse(Y), double_divide(multiply(inverse(Y), X), Z)), Z) = X. 0.21/0.50 Proof: 0.21/0.50 double_divide(multiply(inverse(Y), double_divide(multiply(inverse(Y), X), Z)), Z) 0.21/0.50 = { by lemma 5 } 0.21/0.50 double_divide(multiply(inverse(Y), double_divide(multiply(inverse(Y), double_divide(multiply(inverse(?), ?), inverse(X))), Z)), Z) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(inverse(double_divide(double_divide(multiply(inverse(Y), double_divide(multiply(inverse(?), ?), inverse(X))), Z), inverse(Y))), Z) 0.21/0.50 = { by axiom 1 (single_axiom) } 0.21/0.50 double_divide(inverse(double_divide(double_divide(multiply(inverse(Y), double_divide(multiply(inverse(?), ?), inverse(X))), Z), inverse(double_divide(inverse(double_divide(double_divide(multiply(inverse(?), ?), inverse(X)), inverse(double_divide(multiply(inverse(?), ?), inverse(Y))))), inverse(X))))), Z) 0.21/0.50 = { by lemma 5 } 0.21/0.50 double_divide(inverse(double_divide(double_divide(multiply(inverse(Y), double_divide(multiply(inverse(?), ?), inverse(X))), Z), inverse(double_divide(inverse(double_divide(double_divide(multiply(inverse(?), ?), inverse(X)), inverse(Y))), inverse(X))))), Z) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(inverse(double_divide(double_divide(multiply(inverse(Y), double_divide(multiply(inverse(?), ?), inverse(X))), Z), inverse(double_divide(multiply(inverse(Y), double_divide(multiply(inverse(?), ?), inverse(X))), inverse(X))))), Z) 0.21/0.50 = { by axiom 1 (single_axiom) } 0.21/0.50 X 0.21/0.50 0.21/0.50 Lemma 22: double_divide(multiply(inverse(Y), double_divide(inverse(Y), X)), X) = multiply(inverse(?), ?). 0.21/0.50 Proof: 0.21/0.50 double_divide(multiply(inverse(Y), double_divide(inverse(Y), X)), X) 0.21/0.50 = { by lemma 6 } 0.21/0.50 double_divide(multiply(inverse(Y), double_divide(multiply(inverse(Y), multiply(inverse(?), ?)), X)), X) 0.21/0.50 = { by lemma 21 } 0.21/0.50 multiply(inverse(?), ?) 0.21/0.50 0.21/0.50 Lemma 23: multiply(multiply(inverse(?), ?), X) = X. 0.21/0.50 Proof: 0.21/0.50 multiply(multiply(inverse(?), ?), X) 0.21/0.50 = { by lemma 22 } 0.21/0.50 multiply(double_divide(multiply(inverse(?), double_divide(inverse(?), ?)), ?), X) 0.21/0.50 = { by lemma 7 } 0.21/0.50 multiply(double_divide(multiply(inverse(?), ?), multiply(?, multiply(inverse(?), double_divide(inverse(?), ?)))), X) 0.21/0.50 = { by lemma 17 } 0.21/0.50 multiply(inverse(multiply(multiply(?, multiply(inverse(?), double_divide(inverse(?), ?))), multiply(inverse(?), ?))), X) 0.21/0.50 = { by lemma 15 } 0.21/0.50 double_divide(multiply(multiply(?, multiply(inverse(?), double_divide(inverse(?), ?))), multiply(inverse(?), ?)), inverse(X)) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(multiply(inverse(double_divide(multiply(inverse(?), double_divide(inverse(?), ?)), ?)), multiply(inverse(?), ?)), inverse(X)) 0.21/0.50 = { by lemma 22 } 0.21/0.50 double_divide(multiply(inverse(double_divide(multiply(inverse(?), double_divide(inverse(?), ?)), ?)), double_divide(multiply(inverse(?), double_divide(inverse(?), ?)), ?)), inverse(X)) 0.21/0.50 = { by lemma 5 } 0.21/0.50 X 0.21/0.50 0.21/0.50 Lemma 24: multiply(inverse(X), ?) = multiply(?, inverse(X)). 0.21/0.50 Proof: 0.21/0.50 multiply(inverse(X), ?) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 inverse(double_divide(?, inverse(X))) 0.21/0.50 = { by lemma 10 } 0.21/0.50 multiply(inverse(multiply(inverse(X), double_divide(?, inverse(X)))), inverse(X)) 0.21/0.50 = { by lemma 23 } 0.21/0.50 multiply(inverse(multiply(inverse(X), multiply(multiply(inverse(?), ?), double_divide(?, inverse(X))))), inverse(X)) 0.21/0.50 = { by lemma 3 } 0.21/0.50 multiply(inverse(inverse(?)), inverse(X)) 0.21/0.50 = { by lemma 16 } 0.21/0.50 multiply(?, inverse(X)) 0.21/0.50 0.21/0.50 Lemma 25: double_divide(Z, double_divide(Z, double_divide(X, Y))) = double_divide(X, Y). 0.21/0.50 Proof: 0.21/0.50 double_divide(Z, double_divide(Z, double_divide(X, Y))) 0.21/0.50 = { by lemma 20 } 0.21/0.50 double_divide(Z, double_divide(Z, double_divide(Y, X))) 0.21/0.50 = { by lemma 20 } 0.21/0.50 double_divide(Z, double_divide(double_divide(Y, X), Z)) 0.21/0.50 = { by lemma 20 } 0.21/0.50 double_divide(double_divide(double_divide(Y, X), Z), Z) 0.21/0.50 = { by lemma 5 } 0.21/0.50 double_divide(double_divide(multiply(inverse(multiply(?, inverse(?))), multiply(?, inverse(?))), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by lemma 23 } 0.21/0.50 double_divide(double_divide(multiply(multiply(multiply(inverse(?), ?), inverse(multiply(?, inverse(?)))), multiply(?, inverse(?))), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(double_divide(multiply(inverse(double_divide(inverse(multiply(?, inverse(?))), multiply(inverse(?), ?))), multiply(?, inverse(?))), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by lemma 24 } 0.21/0.50 double_divide(double_divide(multiply(inverse(double_divide(inverse(multiply(?, inverse(?))), multiply(inverse(?), ?))), multiply(inverse(?), ?)), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by lemma 6 } 0.21/0.50 double_divide(double_divide(inverse(double_divide(inverse(multiply(?, inverse(?))), multiply(inverse(?), ?))), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.50 double_divide(double_divide(multiply(multiply(inverse(?), ?), inverse(multiply(?, inverse(?)))), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by lemma 23 } 0.21/0.50 double_divide(double_divide(inverse(multiply(?, inverse(?))), inverse(double_divide(double_divide(Y, X), Z))), Z) 0.21/0.50 = { by lemma 15 } 0.21/0.50 double_divide(multiply(inverse(inverse(multiply(?, inverse(?)))), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.50 = { by lemma 16 } 0.21/0.50 double_divide(multiply(multiply(?, inverse(?)), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.50 = { by lemma 24 } 0.21/0.50 double_divide(multiply(multiply(inverse(?), ?), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.50 = { by lemma 22 } 0.21/0.50 double_divide(multiply(double_divide(multiply(inverse(?), double_divide(inverse(?), ?)), ?), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.50 = { by lemma 6 } 0.21/0.50 double_divide(multiply(double_divide(multiply(inverse(?), double_divide(multiply(inverse(?), multiply(inverse(double_divide(X, Y)), double_divide(X, Y))), ?)), ?), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.50 = { by axiom 2 (multiply) } 0.21/0.51 double_divide(multiply(double_divide(multiply(inverse(?), double_divide(multiply(inverse(?), multiply(multiply(Y, X), double_divide(X, Y))), ?)), ?), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.51 = { by lemma 20 } 0.21/0.51 double_divide(multiply(double_divide(multiply(inverse(?), double_divide(multiply(inverse(?), multiply(multiply(Y, X), double_divide(Y, X))), ?)), ?), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.51 = { by lemma 21 } 0.21/0.51 double_divide(multiply(multiply(multiply(Y, X), double_divide(Y, X)), double_divide(double_divide(Y, X), Z)), Z) 0.21/0.51 = { by lemma 19 } 0.21/0.51 double_divide(X, Y) 0.21/0.51 0.21/0.51 Lemma 26: double_divide(X, double_divide(X, Y)) = Y. 0.21/0.51 Proof: 0.21/0.51 double_divide(X, double_divide(X, Y)) 0.21/0.51 = { by axiom 1 (single_axiom) } 0.21/0.51 double_divide(X, double_divide(X, double_divide(inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))), ?))) 0.21/0.51 = { by lemma 25 } 0.21/0.51 double_divide(inverse(double_divide(double_divide(?, ?), inverse(double_divide(?, inverse(Y))))), ?) 0.21/0.51 = { by axiom 1 (single_axiom) } 0.21/0.53 Y 0.21/0.53 0.21/0.53 Goal 1 (prove_these_axioms_3): multiply(a3, multiply(b3, c3)) = multiply(multiply(a3, b3), c3). 0.21/0.53 Proof: 0.21/0.53 multiply(a3, multiply(b3, c3)) 0.21/0.53 = { by lemma 18 } 0.21/0.53 multiply(a3, multiply(c3, b3)) 0.21/0.53 = { by lemma 18 } 0.21/0.53 multiply(a3, multiply(b3, c3)) 0.21/0.53 = { by lemma 16 } 0.21/0.53 multiply(a3, multiply(b3, inverse(inverse(c3)))) 0.21/0.53 = { by lemma 26 } 0.21/0.53 double_divide(inverse(c3), double_divide(inverse(c3), multiply(a3, multiply(b3, inverse(inverse(c3)))))) 0.21/0.53 = { by lemma 25 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(a3, double_divide(inverse(c3), multiply(a3, multiply(b3, inverse(inverse(c3)))))))) 0.21/0.53 = { by lemma 20 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(double_divide(inverse(c3), multiply(a3, multiply(b3, inverse(inverse(c3))))), a3))) 0.21/0.53 = { by lemma 19 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, double_divide(inverse(c3), multiply(a3, multiply(b3, inverse(inverse(c3)))))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 18 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, double_divide(inverse(c3), multiply(a3, multiply(inverse(inverse(c3)), b3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 18 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, double_divide(inverse(c3), multiply(multiply(inverse(inverse(c3)), b3), a3))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 14 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, double_divide(inverse(c3), double_divide(inverse(c3), multiply(inverse(multiply(multiply(inverse(inverse(c3)), b3), a3)), inverse(inverse(c3)))))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 26 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(multiply(multiply(inverse(inverse(c3)), b3), a3)), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 18 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(multiply(a3, multiply(inverse(inverse(c3)), b3))), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by axiom 2 (multiply) } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(inverse(double_divide(multiply(inverse(inverse(c3)), b3), a3))), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 25 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(inverse(double_divide(inverse(inverse(c3)), double_divide(inverse(inverse(c3)), double_divide(multiply(inverse(inverse(c3)), b3), a3))))), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by axiom 2 (multiply) } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(multiply(double_divide(inverse(inverse(c3)), double_divide(multiply(inverse(inverse(c3)), b3), a3)), inverse(inverse(c3)))), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 18 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(multiply(inverse(inverse(c3)), double_divide(inverse(inverse(c3)), double_divide(multiply(inverse(inverse(c3)), b3), a3)))), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 10 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, inverse(double_divide(inverse(inverse(c3)), double_divide(multiply(inverse(inverse(c3)), b3), a3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by axiom 2 (multiply) } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(double_divide(multiply(inverse(inverse(c3)), b3), a3), inverse(inverse(c3)))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 18 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(multiply(a3, multiply(inverse(inverse(c3)), double_divide(multiply(inverse(inverse(c3)), b3), a3))), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by axiom 2 (multiply) } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(inverse(double_divide(multiply(inverse(inverse(c3)), double_divide(multiply(inverse(inverse(c3)), b3), a3)), a3)), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 21 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, double_divide(multiply(multiply(inverse(b3), ?), double_divide(?, ?)), ?))) 0.21/0.53 = { by lemma 4 } 0.21/0.53 double_divide(inverse(c3), double_divide(a3, b3)) 0.21/0.53 = { by lemma 20 } 0.21/0.53 double_divide(double_divide(a3, b3), inverse(c3)) 0.21/0.53 = { by lemma 15 } 0.21/0.53 multiply(inverse(double_divide(a3, b3)), c3) 0.21/0.53 = { by lemma 18 } 0.21/0.53 multiply(c3, inverse(double_divide(a3, b3))) 0.21/0.53 = { by axiom 2 (multiply) } 0.21/0.53 multiply(c3, multiply(b3, a3)) 0.21/0.53 = { by lemma 18 } 0.21/0.53 multiply(c3, multiply(a3, b3)) 0.21/0.53 = { by lemma 18 } 0.21/0.53 multiply(multiply(a3, b3), c3) 0.21/0.53 % SZS output end Proof 0.21/0.53 0.21/0.53 RESULT: Unsatisfiable (the axioms are contradictory). 0.21/0.53 EOF