Nuprl Lemma : r2-plane-separation1

a,b:ℝ^2. ∀u:{u:ℝ^2| r2-left(u;a;b)} . ∀v:{v:ℝ^2| r2-left(v;b;a)} .
  (∃x:ℝ^2 [((¬((¬a_b_x) ∧ b_x_a) ∧ x_a_b))) ∧ u_x_v)])


Proof




Definitions occuring in Statement :  r2-left: r2-left(p;q;r) rv-be: a_b_c real-vec: ^n all: x:A. B[x] sq_exists: x:A [B[x]] not: ¬A and: P ∧ Q set: {x:A| B[x]}  natural_number: $n
Definitions unfolded in proof :  all: x:A. B[x] member: t ∈ T implies:  Q sq_stable: SqStable(P) squash: T exists: x:A. B[x] sq_exists: x:A [B[x]] and: P ∧ Q cand: c∧ B not: ¬A uall: [x:A]. B[x] nat: le: A ≤ B less_than': less_than'(a;b) false: False prop: uiff: uiff(P;Q) uimplies: supposing a or: P ∨ Q rv-be: a_b_c stable: Stable{P} iff: ⇐⇒ Q

Latex:
\mforall{}a,b:\mBbbR{}\^{}2.  \mforall{}u:\{u:\mBbbR{}\^{}2|  r2-left(u;a;b)\}  .  \mforall{}v:\{v:\mBbbR{}\^{}2|  r2-left(v;b;a)\}  .
    (\mexists{}x:\mBbbR{}\^{}2  [((\mneg{}((\mneg{}a\_b\_x)  \mwedge{}  (\mneg{}b\_x\_a)  \mwedge{}  (\mneg{}x\_a\_b)))  \mwedge{}  u\_x\_v)])



Date html generated: 2020_05_20-PM-01_02_02
Last ObjectModification: 2019_12_11-AM-11_44_28

Theory : reals


Home Index