Nuprl Lemma : in-some-half-cube

k:ℕ. ∀x:ℝ^k. ∀c:ℚCube(k).  (in-rat-cube(k;x;c)  (¬¬(∃h:ℚCube(k). ((↑is-half-cube(k;h;c)) ∧ in-rat-cube(k;x;h)))))


Proof




Definitions occuring in Statement :  in-rat-cube: in-rat-cube(k;p;c) real-vec: ^n nat: assert: b all: x:A. B[x] exists: x:A. B[x] not: ¬A implies:  Q and: P ∧ Q is-half-cube: is-half-cube(k;h;c) rational-cube: Cube(k)
Definitions unfolded in proof :  rev_implies:  Q iff: ⇐⇒ Q band: p ∧b q assert: b bnot: ¬bb sq_type: SQType(T) bfalse: ff is-half-interval: is-half-interval(I;J) ifthenelse: if then else fi  btrue: tt it: unit: Unit bool: 𝔹 rev_uimplies: rev_uimplies(P;Q) uiff: uiff(P;Q) isl: isl(x) squash: T less_than: a < b le: A ≤ B lelt: i ≤ j < k int_seg: {i..j-} stable: Stable{P} uimplies: supposing a guard: {T} cand: c∧ B pi2: snd(t) real-vec: ^n pi1: fst(t) rational-interval: Interval rational-cube: Cube(k) or: P ∨ Q nat: prop: uall: [x:A]. B[x] and: P ∧ Q member: t ∈ T exists: x:A. B[x] in-rat-cube: in-rat-cube(k;p;c) false: False not: ¬A implies:  Q all: x:A. B[x]
Lemmas referenced :  assert_of_band assert_of_bor iff_weakening_uiff iff_transitivity equal_wf rationals_wf member_wf assert-qeq band_wf bool_cases qeq_wf2 bor_wf assert_wf assert-bnot bool_subtype_base bool_wf subtype_base_sq bool_cases_sqequal eqff_to_assert eqtt_to_assert assert-is-half-cube rational-interval_wf bfalse_wf btrue_wf ifthenelse_wf Error :finite-double-negation-shift2,  minimal-not-not-excluded-middle minimal-double-negation-hyp-elim not-rless rleq_weakening_rless rless_wf false_wf qavg_wf rat2real_wf rleq_wf not_wf stable__not int_seg_wf istype-nat real-vec_wf rational-cube_wf istype-void in-rat-cube_wf is-half-cube_wf istype-assert
Rules used in proof :  isect_memberEquality_alt cumulativity instantiate promote_hyp equalityElimination independent_pairEquality imageElimination functionExtensionality dependent_pairFormation_alt lambdaEquality_alt unionElimination inrFormation_alt unionIsType independent_isectElimination independent_pairFormation inlFormation_alt functionEquality because_Cache equalitySymmetry equalityTransitivity equalityIstype applyEquality productEquality unionEquality productElimination rename setElimination natural_numberEquality dependent_functionElimination universeIsType isectElimination extract_by_obid introduction hypothesisEquality inhabitedIsType productIsType functionIsType sqequalRule voidElimination independent_functionElimination hypothesis sqequalHypSubstitution thin cut lambdaFormation_alt sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution

Latex:
\mforall{}k:\mBbbN{}.  \mforall{}x:\mBbbR{}\^{}k.  \mforall{}c:\mBbbQ{}Cube(k).
    (in-rat-cube(k;x;c)  {}\mRightarrow{}  (\mneg{}\mneg{}(\mexists{}h:\mBbbQ{}Cube(k).  ((\muparrow{}is-half-cube(k;h;c))  \mwedge{}  in-rat-cube(k;x;h)))))



Date html generated: 2019_11_04-PM-04_43_09
Last ObjectModification: 2019_10_31-AM-11_04_42

Theory : real!vectors


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