Nuprl Lemma : continuous-rneq

∀I:Interval. ∀f:I ⟶ℝ.  (f[x] continuous for x ∈ I ⇒ (∀a,b:{x:ℝ| x ∈ I} .  (f[a] ≠ f[b] ⇒ a ≠ b)))


Proof




Definitions occuring in Statement :  continuous: f[x] continuous for x ∈ I,  rfun: I ⟶ℝ,  i-member: r ∈ I,  interval: Interval,  rneq: x ≠ y,  real: ℝ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  set: {x:A| B[x]} 
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  uall: ∀[x:A]. B[x],  so_apply: x[s],  rfun: I ⟶ℝ,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  prop: ℙ,  exists: ∃x:A. B[x],  cand: A c∧ B,  sq_stable: SqStable(P),  squash: ↓T,  so_lambda: λ2x.t[x],  label: ...$L... t,  rneq: x ≠ y,  or: P ∨ Q,  guard: {T},  uimplies: b supposing a,  continuous: f[x] continuous for x ∈ I,  sq_exists: ∃x:{A| B[x]},  nat_plus: ℕ+,  rless: x < y,  decidable: Dec(P),  satisfiable_int_formula: satisfiable_int_formula(fmla),  false: False,  not: ¬A,  top: Top,  subtype_rel: A ⊆r B,  rleq: x ≤ y,  rnonneg: rnonneg(x),  le: A ≤ B
Lemmas referenced :  rneq-iff-rabs,  rless_irreflexivity,  rless_transitivity1,  rleq_weakening_rless,  not-rless,  sq_stable__rleq,  sq_stable__all,  sq_stable__rless,  sq_stable__and,  squash_wf,  nat_plus_wf,  less_than'_wf,  int_formula_prop_wf,  int_term_value_var_lemma,  int_term_value_constant_lemma,  int_formula_prop_less_lemma,  int_formula_prop_not_lemma,  int_formula_prop_and_lemma,  itermVar_wf,  itermConstant_wf,  intformless_wf,  intformnot_wf,  intformand_wf,  satisfiable-full-omega-tt,  decidable__lt,  nat_plus_properties,  rless-int,  rdiv_wf,  i-member-approx,  rleq_wf,  all_wf,  i-approx_wf,  icompact_wf,  i-approx-compact,  req_weakening,  radd-zero-both,  rless_functionality,  or_wf,  radd_wf,  interval_wf,  rfun_wf,  continuous_wf,  i-member_wf,  real_wf,  set_wf,  rneq_wf,  sq_stable__i-member,  i-approx-containing2,  rless_wf,  int-to-real_wf,  rabs-difference-lower-bound,  rsub_wf,  rabs_wf,  small-reciprocal-real
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  lemma_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  dependent_set_memberEquality,  isectElimination,  applyEquality,  sqequalRule,  hypothesisEquality,  hypothesis,  natural_numberEquality,  productElimination,  independent_functionElimination,  setElimination,  rename,  introduction,  imageMemberEquality,  baseClosed,  imageElimination,  independent_pairFormation,  lambdaEquality,  setEquality,  unionElimination,  inrFormation,  inlFormation,  because_Cache,  addLevel,  orFunctionality,  independent_isectElimination,  isect_memberEquality,  functionEquality,  dependent_pairFormation,  int_eqEquality,  intEquality,  voidElimination,  voidEquality,  computeAll,  minusEquality,  independent_pairEquality,  axiomEquality,  equalityTransitivity,  equalitySymmetry

Latex:
\mforall{}I:Interval.  \mforall{}f:I  {}\mrightarrow{}\mBbbR{}.    (f[x]  continuous  for  x  \mmember{}  I  {}\mRightarrow{}  (\mforall{}a,b:\{x:\mBbbR{}|  x  \mmember{}  I\}  .    (f[a]  \mneq{}  f[b]  {}\mRightarrow{}  a  \mneq{}  b)))



Date html generated: 2016_05_18-AM-09_08_58
Last ObjectModification: 2016_01_17-AM-02_37_40

Theory : reals


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