Nuprl Lemma : qsqrt-property

[r:{r:ℚ0 ≤ r} ]. ∀[n:ℕ+].  |(qsqrt(r;n) qsqrt(r;n)) r| < (1/n)


Proof




Definitions occuring in Statement :  qsqrt: qsqrt(r;n) qabs: |r| qle: r ≤ s qless: r < s qsub: s qdiv: (r/s) qmul: s rationals: nat_plus: + uall: [x:A]. B[x] set: {x:A| B[x]}  natural_number: $n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T qsqrt: qsqrt(r;n) subtype_rel: A ⊆B all: x:A. B[x] prop: so_lambda: λ2x.t[x] and: P ∧ Q nat_plus: + so_apply: x[s] uimplies: supposing a int_nzero: -o implies:  Q nequal: a ≠ b ∈  not: ¬A false: False satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] top: Top sq_exists: x:A [B[x]] sq_stable: SqStable(P) squash: T
Lemmas referenced :  approximate-qsqrt-ext subtype_rel_self rationals_wf qle_wf all_wf nat_plus_wf sq_exists_wf qless_wf qabs_wf qsub_wf qmul_wf qdiv_wf subtype_rel_set less_than_wf int-subtype-rationals int_nzero-rational subtype_rel_sets nequal_wf full-omega-unsat intformand_wf intformeq_wf itermVar_wf itermConstant_wf intformless_wf int_formula_prop_and_lemma int_formula_prop_eq_lemma int_term_value_var_lemma int_term_value_constant_lemma int_formula_prop_less_lemma int_formula_prop_wf equal-wf-base int_subtype_base equal_wf qless_witness qsqrt_wf set_wf sq_stable_from_decidable decidable__qless
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut applyEquality thin instantiate extract_by_obid hypothesis sqequalRule sqequalHypSubstitution isectElimination functionEquality setEquality natural_numberEquality because_Cache hypothesisEquality lambdaFormation setElimination rename lambdaEquality productEquality dependent_functionElimination intEquality independent_isectElimination approximateComputation independent_functionElimination dependent_pairFormation int_eqEquality isect_memberEquality voidElimination voidEquality independent_pairFormation baseClosed equalityTransitivity equalitySymmetry productElimination imageMemberEquality imageElimination

Latex:
\mforall{}[r:\{r:\mBbbQ{}|  0  \mleq{}  r\}  ].  \mforall{}[n:\mBbbN{}\msupplus{}].    |(qsqrt(r;n)  *  qsqrt(r;n))  -  r|  <  (1/n)



Date html generated: 2018_05_22-AM-00_30_29
Last ObjectModification: 2018_05_19-PM-04_10_06

Theory : rationals


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