0.12/0.12 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.12/0.13 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.13/0.34 % Computer : n012.cluster.edu 0.13/0.34 % Model : x86_64 x86_64 0.13/0.34 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.13/0.34 % Memory : 8042.1875MB 0.13/0.34 % OS : Linux 3.10.0-693.el7.x86_64 0.13/0.34 % CPULimit : 180 0.13/0.34 % DateTime : Thu Aug 29 10:23:12 EDT 2019 0.13/0.34 % CPUTime : 0.13/0.38 % SZS status Unsatisfiable 0.13/0.38 0.13/0.38 % SZS output start Proof 0.13/0.38 Take the following subset of the input axioms: 0.13/0.39 fof(multiply, axiom, ![A, B]: inverse(double_divide(B, A))=multiply(A, B)). 0.13/0.39 fof(prove_these_axioms_2, negated_conjecture, a2!=multiply(multiply(inverse(b2), b2), a2)). 0.13/0.39 fof(single_axiom, axiom, ![A, B, C]: inverse(double_divide(inverse(double_divide(A, inverse(double_divide(B, double_divide(A, C))))), C))=B). 0.13/0.39 0.13/0.39 Now clausify the problem and encode Horn clauses using encoding 3 of 0.13/0.39 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 0.13/0.39 We repeatedly replace C & s=t => u=v by the two clauses: 0.13/0.39 fresh(y, y, x1...xn) = u 0.13/0.39 C => fresh(s, t, x1...xn) = v 0.13/0.39 where fresh is a fresh function symbol and x1..xn are the free 0.13/0.39 variables of u and v. 0.13/0.39 A predicate p(X) is encoded as p(X)=true (this is sound, because the 0.13/0.39 input problem has no model of domain size 1). 0.13/0.39 0.13/0.39 The encoding turns the above axioms into the following unit equations and goals: 0.13/0.39 0.13/0.39 Axiom 1 (multiply): inverse(double_divide(X, Y)) = multiply(Y, X). 0.13/0.40 Axiom 2 (single_axiom): inverse(double_divide(inverse(double_divide(X, inverse(double_divide(Y, double_divide(X, Z))))), Z)) = Y. 0.13/0.40 0.13/0.40 Lemma 3: multiply(Z, multiply(multiply(double_divide(X, Z), Y), X)) = Y. 0.13/0.40 Proof: 0.13/0.40 multiply(Z, multiply(multiply(double_divide(X, Z), Y), X)) 0.13/0.40 = { by axiom 1 (multiply) } 0.13/0.40 multiply(Z, multiply(inverse(double_divide(Y, double_divide(X, Z))), X)) 0.13/0.40 = { by axiom 1 (multiply) } 0.13/0.40 multiply(Z, inverse(double_divide(X, inverse(double_divide(Y, double_divide(X, Z)))))) 0.13/0.40 = { by axiom 1 (multiply) } 0.13/0.40 inverse(double_divide(inverse(double_divide(X, inverse(double_divide(Y, double_divide(X, Z))))), Z)) 0.13/0.40 = { by axiom 2 (single_axiom) } 0.13/0.40 Y 0.13/0.40 0.13/0.40 Lemma 4: multiply(multiply(double_divide(X, double_divide(Y, Z)), W), X) = multiply(Z, multiply(W, Y)). 0.13/0.40 Proof: 0.13/0.40 multiply(multiply(double_divide(X, double_divide(Y, Z)), W), X) 0.13/0.40 = { by lemma 3 } 0.13/0.40 multiply(Z, multiply(multiply(double_divide(Y, Z), multiply(multiply(double_divide(X, double_divide(Y, Z)), W), X)), Y)) 0.13/0.40 = { by lemma 3 } 0.13/0.40 multiply(Z, multiply(W, Y)) 0.13/0.40 0.13/0.40 Lemma 5: multiply(double_divide(Y, Z), multiply(Z, multiply(X, Y))) = X. 0.13/0.40 Proof: 0.13/0.40 multiply(double_divide(Y, Z), multiply(Z, multiply(X, Y))) 0.13/0.40 = { by lemma 4 } 0.13/0.40 multiply(double_divide(Y, Z), multiply(multiply(double_divide(?, double_divide(Y, Z)), X), ?)) 0.13/0.40 = { by lemma 3 } 0.13/0.40 X 0.13/0.40 0.13/0.40 Lemma 6: multiply(double_divide(multiply(Y, Z), double_divide(Z, X)), Y) = X. 0.13/0.40 Proof: 0.13/0.40 multiply(double_divide(multiply(Y, Z), double_divide(Z, X)), Y) 0.13/0.40 = { by lemma 5 } 0.13/0.40 multiply(double_divide(multiply(Y, Z), double_divide(Z, X)), multiply(double_divide(Z, X), multiply(X, multiply(Y, Z)))) 0.13/0.40 = { by lemma 5 } 0.13/0.40 X 0.13/0.40 0.13/0.40 Lemma 7: multiply(double_divide(X, W), multiply(W, Z)) = double_divide(multiply(X, ?), double_divide(?, Z)). 0.13/0.40 Proof: 0.13/0.40 multiply(double_divide(X, W), multiply(W, Z)) 0.13/0.40 = { by lemma 6 } 0.13/0.40 multiply(double_divide(X, W), multiply(W, multiply(double_divide(multiply(X, ?), double_divide(?, Z)), X))) 0.13/0.40 = { by lemma 5 } 0.13/0.40 double_divide(multiply(X, ?), double_divide(?, Z)) 0.13/0.40 0.13/0.40 Lemma 8: double_divide(multiply(X, ?), double_divide(?, multiply(Y, X))) = Y. 0.13/0.40 Proof: 0.13/0.40 double_divide(multiply(X, ?), double_divide(?, multiply(Y, X))) 0.13/0.40 = { by lemma 7 } 0.13/0.40 multiply(double_divide(X, ?), multiply(?, multiply(Y, X))) 0.13/0.40 = { by lemma 5 } 0.13/0.40 Y 0.13/0.40 0.13/0.40 Lemma 9: multiply(double_divide(?, multiply(X, Y)), multiply(Y, ?)) = inverse(X). 0.13/0.40 Proof: 0.13/0.40 multiply(double_divide(?, multiply(X, Y)), multiply(Y, ?)) 0.13/0.40 = { by axiom 1 (multiply) } 0.13/0.40 inverse(double_divide(multiply(Y, ?), double_divide(?, multiply(X, Y)))) 0.13/0.40 = { by lemma 8 } 0.13/0.40 inverse(X) 0.13/0.40 0.13/0.40 Lemma 10: double_divide(multiply(multiply(Y, multiply(Z, X)), ?), double_divide(?, Z)) = double_divide(X, Y). 0.13/0.40 Proof: 0.13/0.40 double_divide(multiply(multiply(Y, multiply(Z, X)), ?), double_divide(?, Z)) 0.13/0.40 = { by lemma 7 } 0.13/0.40 multiply(double_divide(multiply(Y, multiply(Z, X)), ?), multiply(?, Z)) 0.13/0.40 = { by lemma 5 } 0.13/0.40 multiply(double_divide(multiply(Y, multiply(Z, X)), ?), multiply(?, multiply(double_divide(X, Y), multiply(Y, multiply(Z, X))))) 0.13/0.40 = { by lemma 5 } 0.13/0.40 double_divide(X, Y) 0.13/0.40 0.13/0.40 Lemma 11: multiply(double_divide(?, X), multiply(multiply(Y, multiply(X, Z)), ?)) = multiply(Y, Z). 0.13/0.40 Proof: 0.13/0.40 multiply(double_divide(?, X), multiply(multiply(Y, multiply(X, Z)), ?)) 0.13/0.40 = { by axiom 1 (multiply) } 0.13/0.41 inverse(double_divide(multiply(multiply(Y, multiply(X, Z)), ?), double_divide(?, X))) 0.13/0.41 = { by lemma 10 } 0.13/0.41 inverse(double_divide(Z, Y)) 0.13/0.41 = { by axiom 1 (multiply) } 0.13/0.41 multiply(Y, Z) 0.13/0.41 0.13/0.41 Lemma 12: multiply(double_divide(?, double_divide(?, X)), Y) = multiply(X, Y). 0.13/0.41 Proof: 0.13/0.41 multiply(double_divide(?, double_divide(?, X)), Y) 0.13/0.41 = { by lemma 11 } 0.13/0.41 multiply(double_divide(?, X), multiply(multiply(double_divide(?, double_divide(?, X)), multiply(X, Y)), ?)) 0.13/0.41 = { by lemma 3 } 0.13/0.41 multiply(X, Y) 0.13/0.41 0.13/0.41 Lemma 13: multiply(double_divide(?, X), ?) = inverse(X). 0.13/0.41 Proof: 0.13/0.41 multiply(double_divide(?, X), ?) 0.13/0.41 = { by axiom 1 (multiply) } 0.13/0.41 inverse(double_divide(?, double_divide(?, X))) 0.13/0.41 = { by lemma 9 } 0.13/0.41 multiply(double_divide(?, multiply(double_divide(?, double_divide(?, X)), ?)), multiply(?, ?)) 0.13/0.41 = { by lemma 12 } 0.13/0.41 multiply(double_divide(?, multiply(X, ?)), multiply(?, ?)) 0.13/0.41 = { by lemma 9 } 0.13/0.41 inverse(X) 0.13/0.41 0.13/0.41 Lemma 14: multiply(multiply(X, Y), ?) = multiply(X, multiply(Y, ?)). 0.13/0.41 Proof: 0.13/0.41 multiply(multiply(X, Y), ?) 0.13/0.41 = { by lemma 12 } 0.13/0.41 multiply(multiply(double_divide(?, double_divide(?, X)), Y), ?) 0.13/0.41 = { by lemma 4 } 0.13/0.41 multiply(X, multiply(Y, ?)) 0.13/0.41 0.13/0.41 Lemma 15: multiply(Y, ?) = multiply(?, Y). 0.13/0.41 Proof: 0.13/0.41 multiply(Y, ?) 0.13/0.41 = { by lemma 3 } 0.13/0.41 multiply(?, multiply(multiply(double_divide(?, ?), multiply(Y, ?)), ?)) 0.13/0.41 = { by lemma 14 } 0.13/0.41 multiply(?, multiply(multiply(multiply(double_divide(?, ?), Y), ?), ?)) 0.13/0.41 = { by axiom 1 (multiply) } 0.13/0.41 multiply(?, multiply(multiply(inverse(double_divide(Y, double_divide(?, ?))), ?), ?)) 0.13/0.41 = { by lemma 4 } 0.13/0.41 multiply(multiply(double_divide(Y, double_divide(?, ?)), multiply(inverse(double_divide(Y, double_divide(?, ?))), ?)), Y) 0.13/0.41 = { by lemma 13 } 0.13/0.41 multiply(multiply(double_divide(Y, double_divide(?, ?)), multiply(multiply(double_divide(?, double_divide(Y, double_divide(?, ?))), ?), ?)), Y) 0.13/0.41 = { by lemma 3 } 0.13/0.41 multiply(?, Y) 0.13/0.41 0.13/0.41 Lemma 16: multiply(X, multiply(?, Y)) = multiply(?, multiply(X, Y)). 0.13/0.41 Proof: 0.13/0.41 multiply(X, multiply(?, Y)) 0.13/0.41 = { by lemma 4 } 0.13/0.41 multiply(multiply(double_divide(?, double_divide(Y, X)), ?), ?) 0.13/0.41 = { by lemma 13 } 0.13/0.41 multiply(inverse(double_divide(Y, X)), ?) 0.13/0.41 = { by lemma 15 } 0.13/0.41 multiply(?, inverse(double_divide(Y, X))) 0.13/0.41 = { by axiom 1 (multiply) } 0.13/0.41 multiply(?, multiply(X, Y)) 0.13/0.41 0.13/0.41 Lemma 17: multiply(?, multiply(X, multiply(double_divide(?, X), Z))) = Z. 0.13/0.41 Proof: 0.13/0.41 multiply(?, multiply(X, multiply(double_divide(?, X), Z))) 0.13/0.41 = { by lemma 16 } 0.13/0.41 multiply(X, multiply(?, multiply(double_divide(?, X), Z))) 0.13/0.41 = { by lemma 16 } 0.13/0.41 multiply(X, multiply(double_divide(?, X), multiply(?, Z))) 0.13/0.41 = { by lemma 15 } 0.13/0.41 multiply(X, multiply(double_divide(?, X), multiply(Z, ?))) 0.13/0.41 = { by lemma 4 } 0.13/0.41 multiply(X, multiply(multiply(double_divide(?, double_divide(?, double_divide(?, X))), Z), ?)) 0.13/0.41 = { by lemma 12 } 0.13/0.41 multiply(double_divide(?, double_divide(?, X)), multiply(multiply(double_divide(?, double_divide(?, double_divide(?, X))), Z), ?)) 0.13/0.41 = { by lemma 3 } 0.20/0.42 Z 0.20/0.42 0.20/0.42 Lemma 18: multiply(X, inverse(multiply(Y, X))) = inverse(Y). 0.20/0.42 Proof: 0.20/0.42 multiply(X, inverse(multiply(Y, X))) 0.20/0.42 = { by lemma 13 } 0.20/0.42 multiply(X, multiply(double_divide(?, multiply(Y, X)), ?)) 0.20/0.42 = { by lemma 3 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(X, multiply(double_divide(?, multiply(Y, X)), ?))), ?)) 0.20/0.42 = { by lemma 11 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(?, multiply(X, multiply(double_divide(?, multiply(Y, X)), ?)))), ?)), ?)) 0.20/0.42 = { by lemma 16 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(X, multiply(?, multiply(double_divide(?, multiply(Y, X)), ?)))), ?)), ?)) 0.20/0.42 = { by lemma 16 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(X, multiply(double_divide(?, multiply(Y, X)), multiply(?, ?)))), ?)), ?)) 0.20/0.42 = { by lemma 14 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(X, multiply(multiply(double_divide(?, multiply(Y, X)), ?), ?))), ?)), ?)) 0.20/0.42 = { by lemma 11 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(X, multiply(multiply(double_divide(?, X), multiply(multiply(double_divide(?, multiply(Y, X)), multiply(X, ?)), ?)), ?))), ?)), ?)) 0.20/0.42 = { by lemma 3 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, multiply(Y, X)), multiply(X, ?)), ?)), ?)), ?)) 0.20/0.42 = { by lemma 14 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(double_divide(?, multiply(Y, X)), multiply(multiply(X, ?), ?))), ?)), ?)) 0.20/0.42 = { by lemma 14 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(double_divide(?, multiply(Y, X)), multiply(X, multiply(?, ?)))), ?)), ?)) 0.20/0.42 = { by lemma 16 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(double_divide(?, multiply(Y, X)), multiply(?, multiply(X, ?)))), ?)), ?)) 0.20/0.42 = { by lemma 16 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(?, multiply(double_divide(?, multiply(Y, X)), multiply(X, ?)))), ?)), ?)) 0.20/0.42 = { by lemma 11 } 0.20/0.42 multiply(?, multiply(multiply(double_divide(?, ?), multiply(double_divide(?, multiply(Y, X)), multiply(X, ?))), ?)) 0.20/0.42 = { by lemma 3 } 0.20/0.42 multiply(double_divide(?, multiply(Y, X)), multiply(X, ?)) 0.20/0.42 = { by lemma 9 } 0.20/0.42 inverse(Y) 0.20/0.42 0.20/0.42 Lemma 19: double_divide(?, double_divide(?, X)) = X. 0.20/0.42 Proof: 0.20/0.42 double_divide(?, double_divide(?, X)) 0.20/0.42 = { by lemma 5 } 0.20/0.42 multiply(double_divide(?, ?), multiply(?, multiply(double_divide(?, double_divide(?, X)), ?))) 0.20/0.42 = { by lemma 12 } 0.20/0.42 multiply(double_divide(?, ?), multiply(?, multiply(X, ?))) 0.20/0.42 = { by lemma 5 } 0.20/0.42 X 0.20/0.42 0.20/0.42 Lemma 20: double_divide(multiply(X, Y), double_divide(Y, Z)) = double_divide(multiply(X, ?), double_divide(?, Z)). 0.20/0.42 Proof: 0.20/0.42 double_divide(multiply(X, Y), double_divide(Y, Z)) 0.20/0.42 = { by lemma 5 } 0.20/0.42 multiply(double_divide(X, W), multiply(W, multiply(double_divide(multiply(X, Y), double_divide(Y, Z)), X))) 0.20/0.42 = { by lemma 6 } 0.20/0.42 multiply(double_divide(X, W), multiply(W, Z)) 0.20/0.42 = { by lemma 6 } 0.20/0.42 multiply(double_divide(X, W), multiply(W, multiply(double_divide(multiply(X, ?), double_divide(?, Z)), X))) 0.20/0.42 = { by lemma 5 } 0.20/0.42 double_divide(multiply(X, ?), double_divide(?, Z)) 0.20/0.42 0.20/0.42 Lemma 21: multiply(double_divide(X, Y), multiply(Z, X)) = multiply(double_divide(?, Y), multiply(Z, ?)). 0.20/0.42 Proof: 0.20/0.42 multiply(double_divide(X, Y), multiply(Z, X)) 0.20/0.42 = { by axiom 1 (multiply) } 0.20/0.42 inverse(double_divide(multiply(Z, X), double_divide(X, Y))) 0.20/0.42 = { by lemma 20 } 0.20/0.42 inverse(double_divide(multiply(Z, ?), double_divide(?, Y))) 0.20/0.42 = { by axiom 1 (multiply) } 0.20/0.42 multiply(double_divide(?, Y), multiply(Z, ?)) 0.20/0.42 0.20/0.42 Lemma 22: double_divide(X, double_divide(X, Y)) = double_divide(?, double_divide(?, Y)). 0.20/0.42 Proof: 0.20/0.42 double_divide(X, double_divide(X, Y)) 0.20/0.42 = { by lemma 10 } 0.20/0.42 double_divide(multiply(multiply(double_divide(X, Y), multiply(Z, X)), ?), double_divide(?, Z)) 0.20/0.42 = { by lemma 21 } 0.20/0.42 double_divide(multiply(multiply(double_divide(?, Y), multiply(Z, ?)), ?), double_divide(?, Z)) 0.20/0.42 = { by lemma 10 } 0.20/0.42 double_divide(?, double_divide(?, Y)) 0.20/0.42 0.20/0.42 Lemma 23: double_divide(Y, double_divide(?, Y)) = ?. 0.20/0.42 Proof: 0.20/0.42 double_divide(Y, double_divide(?, Y)) 0.20/0.42 = { by lemma 3 } 0.20/0.42 double_divide(multiply(?, multiply(multiply(double_divide(?, ?), Y), ?)), double_divide(?, Y)) 0.20/0.42 = { by lemma 14 } 0.20/0.42 double_divide(multiply(multiply(?, multiply(double_divide(?, ?), Y)), ?), double_divide(?, Y)) 0.20/0.42 = { by lemma 7 } 0.20/0.42 multiply(double_divide(multiply(?, multiply(double_divide(?, ?), Y)), ?), multiply(?, Y)) 0.20/0.42 = { by lemma 17 } 0.20/0.42 multiply(double_divide(multiply(?, multiply(double_divide(?, ?), Y)), ?), multiply(?, multiply(?, multiply(?, multiply(double_divide(?, ?), Y))))) 0.20/0.42 = { by lemma 5 } 0.20/0.43 ? 0.20/0.43 0.20/0.43 Lemma 24: multiply(X, Y) = multiply(Y, X). 0.20/0.43 Proof: 0.20/0.43 multiply(X, Y) 0.20/0.43 = { by lemma 3 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), multiply(X, Y)), ?)) 0.20/0.43 = { by lemma 11 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(?, multiply(X, Y))), ?)), ?)) 0.20/0.43 = { by lemma 15 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(multiply(X, Y), ?)), ?)), ?)) 0.20/0.43 = { by axiom 1 (multiply) } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), inverse(double_divide(?, multiply(X, Y)))), ?)), ?)) 0.20/0.43 = { by lemma 18 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(?, inverse(multiply(double_divide(?, multiply(X, Y)), ?)))), ?)), ?)) 0.20/0.43 = { by lemma 13 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), multiply(multiply(double_divide(?, ?), multiply(?, inverse(inverse(multiply(X, Y))))), ?)), ?)) 0.20/0.43 = { by lemma 11 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), inverse(inverse(multiply(X, Y)))), ?)) 0.20/0.43 = { by lemma 3 } 0.20/0.43 inverse(inverse(multiply(X, Y))) 0.20/0.43 = { by lemma 19 } 0.20/0.43 inverse(inverse(multiply(X, double_divide(?, double_divide(?, Y))))) 0.20/0.43 = { by lemma 22 } 0.20/0.43 inverse(inverse(multiply(X, double_divide(X, double_divide(X, Y))))) 0.20/0.43 = { by lemma 13 } 0.20/0.43 inverse(multiply(double_divide(?, multiply(X, double_divide(X, double_divide(X, Y)))), ?)) 0.20/0.43 = { by lemma 19 } 0.20/0.43 inverse(multiply(double_divide(?, double_divide(?, double_divide(?, multiply(X, double_divide(X, double_divide(X, Y)))))), ?)) 0.20/0.43 = { by lemma 22 } 0.20/0.43 inverse(multiply(double_divide(multiply(X, double_divide(X, double_divide(X, Y))), double_divide(multiply(X, double_divide(X, double_divide(X, Y))), double_divide(?, multiply(X, double_divide(X, double_divide(X, Y)))))), ?)) 0.20/0.43 = { by lemma 23 } 0.20/0.43 inverse(multiply(double_divide(multiply(X, double_divide(X, double_divide(X, Y))), ?), ?)) 0.20/0.43 = { by lemma 23 } 0.20/0.43 inverse(multiply(double_divide(multiply(X, double_divide(X, double_divide(X, Y))), double_divide(double_divide(X, double_divide(X, Y)), double_divide(?, double_divide(X, double_divide(X, Y))))), ?)) 0.20/0.43 = { by lemma 20 } 0.20/0.43 inverse(multiply(double_divide(multiply(X, ?), double_divide(?, double_divide(?, double_divide(X, double_divide(X, Y))))), ?)) 0.20/0.43 = { by lemma 15 } 0.20/0.43 inverse(multiply(double_divide(multiply(?, X), double_divide(?, double_divide(?, double_divide(X, double_divide(X, Y))))), ?)) 0.20/0.43 = { by lemma 19 } 0.20/0.43 inverse(multiply(double_divide(multiply(?, X), double_divide(X, double_divide(X, Y))), ?)) 0.20/0.43 = { by lemma 6 } 0.20/0.43 inverse(double_divide(X, Y)) 0.20/0.43 = { by axiom 1 (multiply) } 0.20/0.43 multiply(Y, X) 0.20/0.43 0.20/0.43 Lemma 25: multiply(double_divide(X, Y), X) = multiply(double_divide(?, Y), ?). 0.20/0.43 Proof: 0.20/0.43 multiply(double_divide(X, Y), X) 0.20/0.43 = { by axiom 1 (multiply) } 0.20/0.43 inverse(double_divide(X, double_divide(X, Y))) 0.20/0.43 = { by lemma 22 } 0.20/0.43 inverse(double_divide(?, double_divide(?, Y))) 0.20/0.43 = { by axiom 1 (multiply) } 0.20/0.43 multiply(double_divide(?, Y), ?) 0.20/0.43 0.20/0.43 Lemma 26: multiply(double_divide(?, X), X) = inverse(?). 0.20/0.43 Proof: 0.20/0.43 multiply(double_divide(?, X), X) 0.20/0.43 = { by lemma 17 } 0.20/0.43 multiply(double_divide(?, multiply(?, multiply(?, multiply(double_divide(?, ?), X)))), X) 0.20/0.43 = { by lemma 3 } 0.20/0.43 multiply(double_divide(?, multiply(?, multiply(?, multiply(double_divide(?, ?), X)))), multiply(?, multiply(multiply(double_divide(?, ?), X), ?))) 0.20/0.43 = { by lemma 14 } 0.20/0.43 multiply(double_divide(?, multiply(?, multiply(?, multiply(double_divide(?, ?), X)))), multiply(multiply(?, multiply(double_divide(?, ?), X)), ?)) 0.20/0.43 = { by lemma 9 } 0.20/0.43 inverse(?) 0.20/0.43 0.20/0.43 Goal 1 (prove_these_axioms_2): a2 = multiply(multiply(inverse(b2), b2), a2). 0.20/0.43 Proof: 0.20/0.43 a2 0.20/0.43 = { by lemma 3 } 0.20/0.43 multiply(?, multiply(multiply(double_divide(?, ?), a2), ?)) 0.20/0.43 = { by lemma 14 } 0.20/0.43 multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?) 0.20/0.43 = { by lemma 3 } 0.20/0.43 multiply(multiply(?, multiply(?, multiply(double_divide(?, ?), a2))), multiply(multiply(double_divide(?, multiply(?, multiply(?, multiply(double_divide(?, ?), a2)))), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)), ?)) 0.20/0.43 = { by lemma 9 } 0.20/0.43 multiply(multiply(?, multiply(?, multiply(double_divide(?, ?), a2))), multiply(inverse(?), ?)) 0.20/0.43 = { by lemma 4 } 0.20/0.43 multiply(multiply(double_divide(multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?), double_divide(?, multiply(?, multiply(?, multiply(double_divide(?, ?), a2))))), inverse(?)), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 8 } 0.20/0.43 multiply(multiply(?, inverse(?)), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 13 } 0.20/0.43 multiply(multiply(?, multiply(double_divide(?, ?), ?)), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 4 } 0.20/0.43 multiply(multiply(multiply(double_divide(?, double_divide(?, ?)), double_divide(?, ?)), ?), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 26 } 0.20/0.43 multiply(multiply(inverse(?), ?), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 26 } 0.20/0.43 multiply(multiply(multiply(double_divide(?, double_divide(?, b2)), double_divide(?, b2)), ?), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 4 } 0.20/0.43 multiply(multiply(b2, multiply(double_divide(?, b2), ?)), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 13 } 0.20/0.43 multiply(multiply(b2, inverse(b2)), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 24 } 0.20/0.43 multiply(multiply(inverse(b2), b2), multiply(multiply(?, multiply(double_divide(?, ?), a2)), ?)) 0.20/0.43 = { by lemma 14 } 0.20/0.43 multiply(multiply(inverse(b2), b2), multiply(?, multiply(multiply(double_divide(?, ?), a2), ?))) 0.20/0.43 = { by lemma 3 } 0.20/0.43 multiply(multiply(inverse(b2), b2), a2) 0.20/0.43 % SZS output end Proof 0.20/0.43 0.20/0.43 RESULT: Unsatisfiable (the axioms are contradictory). 0.20/0.43 EOF