Nuprl Lemma : rinv-limit

x:ℕ ⟶ ℝ. ∀a:ℝ.  (lim n→∞.x[n]  (∀n:ℕx[n] ≠ r0)  a ≠ r0  lim n→∞.(r1/x[n]) (r1/a))


Proof




Definitions occuring in Statement :  converges-to: lim n→∞.x[n] y rdiv: (x/y) rneq: x ≠ y int-to-real: r(n) real: nat: so_apply: x[s] all: x:A. B[x] implies:  Q function: x:A ⟶ B[x] natural_number: $n
Definitions unfolded in proof :  all: x:A. B[x] implies:  Q converges-to: lim n→∞.x[n] y member: t ∈ T uall: [x:A]. B[x] prop: so_apply: x[s] so_lambda: λ2x.t[x] uiff: uiff(P;Q) and: P ∧ Q rev_uimplies: rev_uimplies(P;Q) uimplies: supposing a req_int_terms: t1 ≡ t2 false: False not: ¬A top: Top rsub: y rge: x ≥ y guard: {T} rneq: x ≠ y or: P ∨ Q iff: ⇐⇒ Q rev_implies:  Q less_than: a < b squash: T less_than': less_than'(a;b) true: True nat_plus: + rless: x < y sq_exists: x:A [B[x]] decidable: Dec(P) satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] rdiv: (x/y) sq-all-large: large(n).{P[n]} nat: rat_term_to_real: rat_term_to_real(f;t) rtermDivide: num "/" denom rat_term_ind: rat_term_ind rtermVar: rtermVar(var) rtermConstant: "const" pi1: fst(t) rtermMultiply: left "*" right pi2: snd(t) ge: i ≥  subtype_rel: A ⊆B absval: |i| cand: c∧ B int_nzero: -o nequal: a ≠ b ∈  sq_type: SQType(T)
Lemmas referenced :  rneq_wf int-to-real_wf istype-nat converges-to_wf real_wf radd-preserves-rleq rsub_wf rabs_wf radd_wf rminus_wf itermSubtract_wf itermAdd_wf itermVar_wf itermMinus_wf rleq_functionality radd_functionality req_weakening rabs_functionality req-iff-rsub-is-0 real_polynomial_null istype-int real_term_value_sub_lemma istype-void real_term_value_add_lemma real_term_value_var_lemma real_term_value_const_lemma real_term_value_minus_lemma rleq_weakening_equal rabs-difference-symmetry rleq_functionality_wrt_implies r-triangle-inequality rabs-neq-zero rmul_preserves_rless rdiv_wf rless-int rless_wf rless-int-fractions2 nat_plus_properties decidable__lt full-omega-unsat intformnot_wf intformless_wf itermConstant_wf int_formula_prop_not_lemma int_formula_prop_less_lemma int_term_value_constant_lemma int_formula_prop_wf istype-less_than rmul_wf rinv_wf2 itermMultiply_wf rless_functionality req_transitivity rinv-mul-as-rdiv real_term_value_mul_lemma small-reciprocal-real istype-le assert-rat-term-eq2 rtermMultiply_wf rtermDivide_wf rtermConstant_wf rtermVar_wf rless_transitivity2 nat_properties intformand_wf int_formula_prop_and_lemma int_term_value_var_lemma radd-preserves-rless squash_wf true_wf radd_comm_eq subtype_rel_self iff_weakening_equal rmul-rinv3 radd_comm nat_plus_wf int_term_value_mul_lemma rneq_functionality rmul-int rneq-int intformeq_wf int_formula_prop_eq_lemma set_subtype_base less_than_wf int_subtype_base rmul_functionality req_inversion rinv_functionality2 rinv-of-rmul sq-all-large-and rleq_wf rpositive-rless rabs-positive absval_wf rabs-rmul rabs-rdiv rabs-int rmul_preserves_rleq rinv-as-rdiv rmul-rinv rleq_weakening_rless rabs-rmul-rleq square-nonzero req-int-fractions nequal_wf nat_plus_inc_int_nzero decidable__equal_int req_functionality rmul-rdiv-cancel5 int_entire_a subtype_base_sq rminus_functionality
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation_alt sqequalHypSubstitution cut universeIsType introduction extract_by_obid isectElimination thin hypothesisEquality natural_numberEquality hypothesis sqequalRule functionIsType applyEquality lambdaEquality_alt because_Cache productElimination independent_isectElimination dependent_functionElimination approximateComputation int_eqEquality equalityTransitivity equalitySymmetry isect_memberEquality_alt voidElimination independent_functionElimination closedConclusion inrFormation_alt independent_pairFormation imageMemberEquality baseClosed dependent_set_memberEquality_alt setElimination rename unionElimination dependent_pairFormation_alt inhabitedIsType imageElimination instantiate universeEquality multiplyEquality equalityIstype baseApply intEquality sqequalBase cumulativity

Latex:
\mforall{}x:\mBbbN{}  {}\mrightarrow{}  \mBbbR{}.  \mforall{}a:\mBbbR{}.    (lim  n\mrightarrow{}\minfty{}.x[n]  =  a  {}\mRightarrow{}  (\mforall{}n:\mBbbN{}.  x[n]  \mneq{}  r0)  {}\mRightarrow{}  a  \mneq{}  r0  {}\mRightarrow{}  lim  n\mrightarrow{}\minfty{}.(r1/x[n])  =  (r1/a))



Date html generated: 2019_10_29-AM-10_22_43
Last ObjectModification: 2019_04_02-PM-04_08_58

Theory : reals


Home Index