Nuprl Lemma : qmul_inv

∀[r:ℚ]. (r * 1/r) = 1 ∈ ℚ supposing ¬(r = 0 ∈ ℚ)


Proof




Definitions occuring in Statement :  qinv: 1/r,  qmul: r * s,  rationals: ℚ,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  not: ¬A,  natural_number: $n,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  not: ¬A,  subtype_rel: A ⊆r B,  uiff: uiff(P;Q),  and: P ∧ Q,  prop: ℙ,  rev_uimplies: rev_uimplies(P;Q),  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  nat_plus: ℕ+,  cand: A c∧ B,  implies: P ⇒ Q,  false: False,  qdiv: (r/s),  ifthenelse: if b then t else f fi ,  btrue: tt,  bfalse: ff,  mk-rational: mk-rational(a;b),  int_nzero: ℤ-o,  nequal: a ≠ b ∈ T ,  satisfiable_int_formula: satisfiable_int_formula(fmla),  top: Top,  decidable: Dec(P),  or: P ∨ Q
Lemmas referenced :  assert-qeq,  qmul_wf,  qinv_wf,  int-subtype-rationals,  assert_wf,  qeq_wf2,  not_wf,  equal-wf-T-base,  rationals_wf,  q-elim,  nat_plus_properties,  equal-wf-base,  int_subtype_base,  qdiv_wf,  qeq-elim,  qmul-elim,  qinv-elim,  neg_assert_of_eq_int,  mk-rational_wf,  satisfiable-full-omega-tt,  intformand_wf,  intformeq_wf,  itermMultiply_wf,  itermVar_wf,  itermConstant_wf,  intformnot_wf,  int_formula_prop_and_lemma,  int_formula_prop_eq_lemma,  int_term_value_mul_lemma,  int_term_value_var_lemma,  int_term_value_constant_lemma,  int_formula_prop_not_lemma,  int_formula_prop_wf,  nequal_wf,  mul_nzero,  intformless_wf,  int_formula_prop_less_lemma,  assert_of_eq_int,  decidable__equal_int
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  because_Cache,  independent_isectElimination,  hypothesis,  addLevel,  impliesFunctionality,  natural_numberEquality,  applyEquality,  sqequalRule,  productElimination,  baseClosed,  independent_pairFormation,  isect_memberEquality,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  dependent_functionElimination,  setElimination,  rename,  hyp_replacement,  Error :applyLambdaEquality,  functionEquality,  independent_functionElimination,  lambdaFormation,  levelHypothesis,  promote_hyp,  impliesLevelFunctionality,  voidElimination,  baseApply,  closedConclusion,  isintReduceTrue,  multiplyEquality,  dependent_set_memberEquality,  dependent_pairFormation,  lambdaEquality,  int_eqEquality,  intEquality,  voidEquality,  computeAll,  unionElimination

Latex:
\mforall{}[r:\mBbbQ{}].  (r  *  1/r)  =  1  supposing  \mneg{}(r  =  0)



Date html generated: 2016_10_25-AM-11_50_58
Last ObjectModification: 2016_07_12-AM-07_47_41

Theory : rationals


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