Nuprl Lemma : rv-congruent-iff2

n:ℕ. ∀a,b,c,d:ℝ^n.  (ab=cd ⇐⇒ ¬((d(a;b) < d(c;d)) ∨ (d(c;d) < d(a;b))))


Proof




Definitions occuring in Statement :  rv-congruent: ab=cd real-vec-dist: d(x;y) real-vec: ^n rless: x < y nat: all: x:A. B[x] iff: ⇐⇒ Q not: ¬A or: P ∨ Q
Definitions unfolded in proof :  all: x:A. B[x] rv-congruent: ab=cd iff: ⇐⇒ Q and: P ∧ Q implies:  Q not: ¬A false: False or: P ∨ Q member: t ∈ T uall: [x:A]. B[x] subtype_rel: A ⊆B prop: rev_implies:  Q rless: x < y sq_exists: x:A [B[x]] nat_plus: + nat: ge: i ≥  less_than: a < b squash: T uimplies: supposing a satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] guard: {T}

Latex:
\mforall{}n:\mBbbN{}.  \mforall{}a,b,c,d:\mBbbR{}\^{}n.    (ab=cd  \mLeftarrow{}{}\mRightarrow{}  \mneg{}((d(a;b)  <  d(c;d))  \mvee{}  (d(c;d)  <  d(a;b))))



Date html generated: 2020_05_20-PM-01_03_27
Last ObjectModification: 2019_12_11-PM-00_54_08

Theory : reals


Home Index