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
Home
Index