Nuprl Lemma : rmin-classical-cases

∀a,b:ℝ.  (¬¬((rmin(a;b) = a) ∨ (rmin(a;b) = b)))


Proof




Definitions occuring in Statement :  rmin: rmin(x;y),  req: x = y,  real: ℝ,  all: ∀x:A. B[x],  not: ¬A,  or: P ∨ Q
Definitions unfolded in proof :  all: ∀x:A. B[x],  not: ¬A,  implies: P ⇒ Q,  false: False,  or: P ∨ Q,  member: t ∈ T,  uall: ∀[x:A]. B[x],  prop: ℙ,  uimplies: b supposing a,  stable: Stable{P},  guard: {T}
Lemmas referenced :  req_wf,  rmin_wf,  istype-void,  real_wf,  stable__false,  false_wf,  rless_wf,  not_wf,  not-rless,  minimal-double-negation-hyp-elim,  minimal-not-not-excluded-middle,  rmin-req2,  rleq_weakening_rless,  rmin-req
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  thin,  because_Cache,  hypothesis,  sqequalHypSubstitution,  independent_functionElimination,  voidElimination,  sqequalRule,  functionIsType,  unionIsType,  universeIsType,  introduction,  extract_by_obid,  isectElimination,  hypothesisEquality,  inhabitedIsType,  unionEquality,  functionEquality,  independent_isectElimination,  unionElimination,  inlFormation_alt,  inrFormation_alt

Latex:
\mforall{}a,b:\mBbbR{}.    (\mneg{}\mneg{}((rmin(a;b)  =  a)  \mvee{}  (rmin(a;b)  =  b)))



Date html generated: 2019_10_29-AM-09_38_40
Last ObjectModification: 2019_07_29-PM-03_11_24

Theory : reals


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