Nuprl Lemma : rcos-bounds

∀x:ℝ. (rcos(x) ∈ [r(-1), r1])


Proof




Definitions occuring in Statement :  rcos: rcos(x),  rccint: [l, u],  i-member: r ∈ I,  int-to-real: r(n),  real: ℝ,  all: ∀x:A. B[x],  minus: -n,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  top: Top,  uall: ∀[x:A]. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  implies: P ⇒ Q,  cand: A c∧ B,  squash: ↓T,  prop: ℙ,  true: True,  subtype_rel: A ⊆r B,  uimplies: b supposing a,  guard: {T}
Lemmas referenced :  rabs-rcos-rleq,  member_rccint_lemma,  istype-void,  rabs-rleq-iff,  rcos_wf,  int-to-real_wf,  rleq_wf,  squash_wf,  true_wf,  rminus-int,  subtype_rel_self,  iff_weakening_equal,  real_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  isect_memberEquality_alt,  voidElimination,  hypothesis,  isectElimination,  natural_numberEquality,  productElimination,  independent_functionElimination,  applyEquality,  lambdaEquality_alt,  imageElimination,  because_Cache,  equalityTransitivity,  equalitySymmetry,  universeIsType,  inhabitedIsType,  sqequalRule,  imageMemberEquality,  baseClosed,  instantiate,  universeEquality,  independent_isectElimination,  independent_pairFormation

Latex:
\mforall{}x:\mBbbR{}.  (rcos(x)  \mmember{}  [r(-1),  r1])



Date html generated: 2019_10_30-AM-11_41_44
Last ObjectModification: 2019_05_23-AM-10_12_42

Theory : reals_2


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