Nuprl Lemma : rpower-nonzero

∀x:ℝ. (x ≠ r0 ⇒ (∀n:ℕ. x^n ≠ r0))


Proof




Definitions occuring in Statement :  rneq: x ≠ y,  rnexp: x^k1,  int-to-real: r(n),  real: ℝ,  nat: ℕ,  all: ∀x:A. B[x],  implies: P ⇒ Q,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  top: Top,  rneq: x ≠ y,  guard: {T},  or: P ∨ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  prop: ℙ,  uall: ∀[x:A]. B[x],  nat: ℕ,  decidable: Dec(P),  uimplies: b supposing a,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  not: ¬A,  so_lambda: λ2x.t[x],  so_apply: x[s],  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  ifthenelse: if b then t else f fi ,  uiff: uiff(P;Q),  bfalse: ff,  sq_type: SQType(T),  bnot: ¬bb,  assert: ↑b,  nequal: a ≠ b ∈ T 
Lemmas referenced :  rnexp_zero_lemma,  rless-int,  rless_wf,  int-to-real_wf,  rneq_wf,  rnexp_wf,  decidable__le,  subtract_wf,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermSubtract_wf,  itermVar_wf,  intformless_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_subtract_lemma,  int_term_value_var_lemma,  int_formula_prop_less_lemma,  int_formula_prop_wf,  le_wf,  set_wf,  less_than_wf,  primrec-wf2,  nat_wf,  real_wf,  eq_int_wf,  bool_wf,  eqtt_to_assert,  assert_of_eq_int,  eqff_to_assert,  equal_wf,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  neg_assert_of_eq_int,  rmul_wf,  intformeq_wf,  int_formula_prop_eq_lemma,  rmul-neq-zero,  rneq_functionality,  rnexp-req,  req_weakening
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  thin,  sqequalRule,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  hypothesis,  inrFormation,  because_Cache,  productElimination,  independent_functionElimination,  independent_pairFormation,  natural_numberEquality,  imageMemberEquality,  hypothesisEquality,  baseClosed,  isectElimination,  rename,  setElimination,  dependent_set_memberEquality,  unionElimination,  independent_isectElimination,  dependent_pairFormation,  lambdaEquality,  int_eqEquality,  intEquality,  computeAll,  equalityElimination,  equalityTransitivity,  equalitySymmetry,  promote_hyp,  instantiate,  cumulativity

Latex:
\mforall{}x:\mBbbR{}.  (x  \mneq{}  r0  {}\mRightarrow{}  (\mforall{}n:\mBbbN{}.  x\^{}n  \mneq{}  r0))



Date html generated: 2017_10_03-AM-08_33_38
Last ObjectModification: 2017_07_28-AM-07_28_27

Theory : reals


Home Index