Nuprl Lemma : absval-diff-symmetry

[x,y:ℤ].  (|x y| |y x|)


Proof




Definitions occuring in Statement :  absval: |i| uall: [x:A]. B[x] subtract: m int: sqequal: t
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a nat: so_lambda: λ2x.t[x] so_apply: x[s] all: x:A. B[x] implies:  Q bool: 𝔹 unit: Unit it: btrue: tt uiff: uiff(P;Q) and: P ∧ Q less_than: a < b less_than': less_than'(a;b) top: Top true: True squash: T not: ¬A false: False prop: decidable: Dec(P) or: P ∨ Q satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] bfalse: ff sq_type: SQType(T) guard: {T} bnot: ¬bb ifthenelse: if then else fi  assert: b
Lemmas referenced :  subtype_base_sq nat_wf set_subtype_base le_wf int_subtype_base absval_unfold subtract_wf lt_int_wf bool_wf eqtt_to_assert assert_of_lt_int top_wf less_than_wf decidable__equal_int satisfiable-full-omega-tt intformand_wf intformnot_wf intformeq_wf itermSubtract_wf itermVar_wf intformless_wf itermConstant_wf int_formula_prop_and_lemma int_formula_prop_not_lemma int_formula_prop_eq_lemma int_term_value_subtract_lemma int_term_value_var_lemma int_formula_prop_less_lemma int_term_value_constant_lemma int_formula_prop_wf decidable__le intformle_wf int_formula_prop_le_lemma eqff_to_assert equal_wf bool_cases_sqequal bool_subtype_base assert-bnot itermMinus_wf int_term_value_minus_lemma
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut thin instantiate extract_by_obid sqequalHypSubstitution isectElimination cumulativity hypothesis independent_isectElimination sqequalRule intEquality lambdaEquality natural_numberEquality hypothesisEquality minusEquality lambdaFormation unionElimination equalityElimination equalityTransitivity equalitySymmetry productElimination because_Cache lessCases sqequalAxiom isect_memberEquality independent_pairFormation voidElimination voidEquality imageMemberEquality baseClosed imageElimination independent_functionElimination dependent_functionElimination dependent_pairFormation int_eqEquality computeAll dependent_set_memberEquality promote_hyp

Latex:
\mforall{}[x,y:\mBbbZ{}].    (|x  -  y|  \msim{}  |y  -  x|)



Date html generated: 2017_04_14-AM-09_13_48
Last ObjectModification: 2017_02_27-PM-03_51_25

Theory : int_2


Home Index