Nuprl Lemma : qabs-positive
∀[r:ℚ]. 0 < |r| supposing ¬(r = 0 ∈ ℚ)
Proof
Definitions occuring in Statement : 
qabs: |r|, 
qless: r < s, 
rationals: ℚ, 
uimplies: b supposing a, 
uall: ∀[x:A]. B[x], 
not: ¬A, 
natural_number: $n, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
subtype_rel: A ⊆r B, 
implies: P ⇒ Q, 
prop: ℙ, 
uiff: uiff(P;Q), 
and: P ∧ Q
Lemmas referenced : 
qpositive-qabs, 
qless_witness, 
int-subtype-rationals, 
qabs_wf, 
not_wf, 
equal_wf, 
rationals_wf, 
assert-qpositive
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
independent_isectElimination, 
hypothesis, 
natural_numberEquality, 
applyEquality, 
sqequalRule, 
independent_functionElimination, 
because_Cache, 
isect_memberEquality, 
equalityTransitivity, 
equalitySymmetry, 
productElimination
Latex:
\mforall{}[r:\mBbbQ{}].  0  <  |r|  supposing  \mneg{}(r  =  0)
Date html generated:
2016_05_15-PM-10_55_12
Last ObjectModification:
2015_12_27-PM-07_52_39
Theory : rationals
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