Nuprl Lemma : not-rv-pos-angle-implies2

∀n:ℕ. ∀a,b,c:ℝ^n.  ((¬rv-pos-angle(n;a;b;c)) ⇒ (¬((¬rv-T(n;a;b;c)) ∧ (¬rv-T(n;b;c;a)) ∧ (¬rv-T(n;c;a;b)))))


Proof




Definitions occuring in Statement :  rv-T: rv-T(n;a;b;c),  rv-pos-angle: rv-pos-angle(n;a;b;c),  real-vec: ℝ^n,  nat: ℕ,  all: ∀x:A. B[x],  not: ¬A,  implies: P ⇒ Q,  and: P ∧ Q
Definitions unfolded in proof :  all: ∀x:A. B[x],  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  prop: ℙ,  and: P ∧ Q,  not: ¬A,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  false: False,  or: P ∨ Q,  cand: A c∧ B
Lemmas referenced :  not-rv-pos-angle-implies,  not_wf,  rv-pos-angle_wf,  real-vec_wf,  nat_wf,  false_wf,  or_wf,  real-vec-sep_wf,  rv-T_wf,  rv-T-iff,  rv-between_wf,  minimal-double-negation-hyp-elim,  minimal-not-not-excluded-middle
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  dependent_functionElimination,  independent_functionElimination,  functionEquality,  productEquality,  because_Cache,  productElimination,  voidElimination,  unionElimination,  independent_pairFormation

Latex:
\mforall{}n:\mBbbN{}.  \mforall{}a,b,c:\mBbbR{}\^{}n.
    ((\mneg{}rv-pos-angle(n;a;b;c))  {}\mRightarrow{}  (\mneg{}((\mneg{}rv-T(n;a;b;c))  \mwedge{}  (\mneg{}rv-T(n;b;c;a))  \mwedge{}  (\mneg{}rv-T(n;c;a;b)))))



Date html generated: 2017_10_03-AM-11_20_11
Last ObjectModification: 2017_06_14-PM-06_12_44

Theory : reals


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