Nuprl Lemma : real-vec-angle-lemma
∀n:ℕ. ∀x,z:ℝ^n.  (d(z;x) < d(z;r(-1)*x) 
⇐⇒ r0 < x⋅z)
Proof
Definitions occuring in Statement : 
real-vec-dist: d(x;y)
, 
dot-product: x⋅y
, 
real-vec-mul: a*X
, 
real-vec: ℝ^n
, 
rless: x < y
, 
int-to-real: r(n)
, 
nat: ℕ
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
minus: -n
, 
natural_number: $n
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
real-vec-dist: d(x;y)
, 
real-vec-norm: ||x||
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
member: t ∈ T
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
rev_implies: P 
⇐ Q
, 
implies: P 
⇒ Q
, 
subtype_rel: A ⊆r B
, 
uimplies: b supposing a
, 
uiff: uiff(P;Q)
, 
req_int_terms: t1 ≡ t2
, 
false: False
, 
not: ¬A
, 
top: Top
, 
less_than: a < b
, 
squash: ↓T
, 
less_than': less_than'(a;b)
, 
true: True
Lemmas referenced : 
rsqrt-rless-iff, 
dot-product-nonneg, 
real-vec-sub_wf, 
dot-product_wf, 
rleq_wf, 
int-to-real_wf, 
real-vec-mul_wf, 
rless_wf, 
rsqrt_wf, 
real_wf, 
req_wf, 
rmul_wf, 
iff_wf, 
real-vec_wf, 
nat_wf, 
dot-product-comm, 
radd_wf, 
rless_functionality, 
rsub_wf, 
itermSubtract_wf, 
itermVar_wf, 
itermAdd_wf, 
itermMultiply_wf, 
itermConstant_wf, 
req-iff-rsub-is-0, 
req_transitivity, 
dot-product-linearity1-sub, 
rsub_functionality, 
req_weakening, 
dot-product-linearity2, 
rmul_functionality, 
real_polynomial_null, 
real_term_value_sub_lemma, 
real_term_value_var_lemma, 
real_term_value_add_lemma, 
real_term_value_mul_lemma, 
real_term_value_const_lemma, 
radd-preserves-rless, 
rmul_preserves_rless, 
rless-int, 
rmul-zero-both, 
rmul_comm
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
addLevel, 
sqequalHypSubstitution, 
productElimination, 
thin, 
independent_pairFormation, 
impliesFunctionality, 
introduction, 
extract_by_obid, 
dependent_functionElimination, 
isectElimination, 
hypothesisEquality, 
hypothesis, 
dependent_set_memberEquality, 
natural_numberEquality, 
because_Cache, 
minusEquality, 
independent_functionElimination, 
applyEquality, 
sqequalRule, 
lambdaEquality, 
setElimination, 
rename, 
setEquality, 
productEquality, 
independent_isectElimination, 
approximateComputation, 
int_eqEquality, 
intEquality, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
imageMemberEquality, 
baseClosed
Latex:
\mforall{}n:\mBbbN{}.  \mforall{}x,z:\mBbbR{}\^{}n.    (d(z;x)  <  d(z;r(-1)*x)  \mLeftarrow{}{}\mRightarrow{}  r0  <  x\mcdot{}z)
Date html generated:
2018_05_22-PM-02_25_51
Last ObjectModification:
2018_03_27-PM-10_36_41
Theory : reals
Home
Index