Nuprl Lemma : r-bound-property

[x:ℝ]. ((r(-r-bound(x)) ≤ x) ∧ (x ≤ r(r-bound(x))))


Proof




Definitions occuring in Statement :  r-bound: r-bound(x) rleq: x ≤ y int-to-real: r(n) real: uall: [x:A]. B[x] and: P ∧ Q minus: -n
Definitions unfolded in proof :  guard: {T} rge: x ≥ y rev_uimplies: rev_uimplies(P;Q) top: Top req_int_terms: t1 ≡ t2 uiff: uiff(P;Q) less_than': less_than'(a;b) rev_implies:  Q iff: ⇐⇒ Q uimplies: supposing a real: false: False not: ¬A le: A ≤ B rnonneg: rnonneg(x) rleq: x ≤ y pi1: fst(t) implies:  Q prop: exists: x:A. B[x] so_apply: x[s] nat_plus: + so_lambda: λ2x.t[x] all: x:A. B[x] subtype_rel: A ⊆B r-bound: r-bound(x) cand: c∧ B and: P ∧ Q member: t ∈ T uall: [x:A]. B[x]
Lemmas referenced :  rleq_transitivity rleq_weakening_equal rleq_functionality_wrt_implies rabs-bounds real_term_value_minus_lemma real_term_value_const_lemma real_term_value_var_lemma real_term_value_mul_lemma real_term_value_sub_lemma real_polynomial_null rminus-int req_weakening req_transitivity rleq_functionality req-iff-rsub-is-0 itermMinus_wf itermConstant_wf itermVar_wf itermMultiply_wf itermSubtract_wf rminus_wf rmul_wf false_wf rleq-int rmul_reverses_rleq r-bound_wf rsub_wf less_than'_wf equal_wf int-to-real_wf rabs_wf rleq_wf nat_plus_wf exists_wf real_wf subtype_rel_self integer-bound
Rules used in proof :  voidEquality isect_memberEquality intEquality int_eqEquality approximateComputation independent_isectElimination axiomEquality natural_numberEquality minusEquality voidElimination independent_pairEquality independent_pairFormation independent_functionElimination dependent_functionElimination equalitySymmetry equalityTransitivity productElimination lambdaFormation because_Cache rename setElimination hypothesisEquality lambdaEquality functionEquality isectElimination sqequalHypSubstitution sqequalRule hypothesis extract_by_obid instantiate thin applyEquality cut introduction isect_memberFormation sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution

Latex:
\mforall{}[x:\mBbbR{}].  ((r(-r-bound(x))  \mleq{}  x)  \mwedge{}  (x  \mleq{}  r(r-bound(x))))



Date html generated: 2018_05_22-PM-01_50_40
Last ObjectModification: 2018_05_21-AM-00_09_25

Theory : reals


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