Nuprl Lemma : qminus-positive

∀[r:ℚ]. uiff(0 < -(r);r < 0)


Proof




Definitions occuring in Statement :  qless: r < s,  qmul: r * s,  rationals: ℚ,  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  minus: -n,  natural_number: $n
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  subtype_rel: A ⊆r B,  guard: {T},  implies: P ⇒ Q,  prop: ℙ,  rev_uimplies: rev_uimplies(P;Q),  true: True,  squash: ↓T,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q
Lemmas referenced :  iff_weakening_equal,  mon_ident_q,  qinverse_q,  qadd_comm_q,  qadd_wf,  rationals_wf,  qless_wf,  int-subtype-rationals,  qless_witness,  qmul_wf,  qadd_preserves_qless
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  independent_pairFormation,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  because_Cache,  minusEquality,  natural_numberEquality,  hypothesis,  applyEquality,  sqequalRule,  hypothesisEquality,  productElimination,  independent_isectElimination,  independent_functionElimination,  independent_pairEquality,  isect_memberEquality,  equalityTransitivity,  equalitySymmetry,  lambdaEquality,  imageElimination,  imageMemberEquality,  baseClosed

Latex:
\mforall{}[r:\mBbbQ{}].  uiff(0  <  -(r);r  <  0)



Date html generated: 2016_05_15-PM-10_54_41
Last ObjectModification: 2016_01_16-PM-09_34_21

Theory : rationals


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