Nuprl Lemma : scale-metric-cauchy
∀[X:Type]. ∀[d:metric(X)].  ∀c:{c:ℝ| r0 < c} . ∀x:ℕ ⟶ X.  (mcauchy(d;n.x n) ⇐⇒ mcauchy(c*d;n.x n))
Proof
Definitions occuring in Statement : 
mcauchy: mcauchy(d;n.x[n]), 
scale-metric: c*d, 
metric: metric(X), 
rless: x < y, 
int-to-real: r(n), 
real: ℝ, 
nat: ℕ, 
uall: ∀[x:A]. B[x], 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
set: {x:A| B[x]} , 
apply: f a, 
function: x:A ⟶ B[x], 
natural_number: $n, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
implies: P ⇒ Q, 
subtype_rel: A ⊆r B, 
metric-leq: d1 ≤ d2, 
uimplies: b supposing a, 
rleq: x ≤ y, 
rnonneg: rnonneg(x), 
le: A ≤ B, 
metric: metric(X), 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
prop: ℙ, 
rev_implies: P ⇐ Q, 
rneq: x ≠ y, 
guard: {T}, 
or: P ∨ Q, 
sq_stable: SqStable(P), 
squash: ↓T, 
less_than: a < b, 
less_than': less_than'(a;b), 
true: True, 
rdiv: (x/y), 
uiff: uiff(P;Q), 
req_int_terms: t1 ≡ t2, 
false: False, 
not: ¬A, 
top: Top, 
scale-metric: c*d, 
mdist: mdist(d;x;y), 
rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced : 
metric-leq-cauchy, 
scale-metric_wf, 
rleq_weakening_equal, 
mdist_wf, 
le_witness_for_triv, 
mcauchy_wf, 
istype-nat, 
rdiv_wf, 
int-to-real_wf, 
sq_stable__rless, 
rless_wf, 
subtype_rel_sets_simple, 
real_wf, 
rleq_wf, 
rleq_weakening_rless, 
metric_wf, 
istype-universe, 
rmul_preserves_rless, 
rmul_wf, 
itermSubtract_wf, 
itermMultiply_wf, 
itermConstant_wf, 
itermVar_wf, 
rinv_wf2, 
rless-int, 
rless_functionality, 
req_transitivity, 
rmul-rinv, 
req-iff-rsub-is-0, 
real_polynomial_null, 
istype-int, 
real_term_value_sub_lemma, 
istype-void, 
real_term_value_mul_lemma, 
real_term_value_const_lemma, 
real_term_value_var_lemma, 
rleq_functionality, 
req_weakening, 
rmul_functionality
Rules used in proof : 
cut, 
introduction, 
extract_by_obid, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
lambdaFormation_alt, 
independent_pairFormation, 
applyEquality, 
because_Cache, 
sqequalRule, 
dependent_functionElimination, 
independent_functionElimination, 
independent_isectElimination, 
lambdaEquality_alt, 
productElimination, 
equalityTransitivity, 
equalitySymmetry, 
functionIsTypeImplies, 
inhabitedIsType, 
universeIsType, 
setElimination, 
rename, 
dependent_set_memberEquality_alt, 
closedConclusion, 
natural_numberEquality, 
inrFormation_alt, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
functionIsType, 
setIsType, 
instantiate, 
universeEquality, 
approximateComputation, 
int_eqEquality, 
isect_memberEquality_alt, 
voidElimination
Latex:
\mforall{}[X:Type].  \mforall{}[d:metric(X)].    \mforall{}c:\{c:\mBbbR{}|  r0  <  c\}  .  \mforall{}x:\mBbbN{}  {}\mrightarrow{}  X.    (mcauchy(d;n.x  n)  \mLeftarrow{}{}\mRightarrow{}  mcauchy(c*d;n.x  n))
Date html generated:
2019_10_30-AM-06_44_55
Last ObjectModification:
2019_10_02-AM-10_56_50
Theory : reals
Home
Index