Nuprl Lemma : rabs-positive
∀x:ℝ. (x ≠ r0 
⇒ rpositive(|x|))
Proof
Definitions occuring in Statement : 
rneq: x ≠ y
, 
rpositive: rpositive(x)
, 
rabs: |x|
, 
int-to-real: r(n)
, 
real: ℝ
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
natural_number: $n
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
top: Top
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
prop: ℙ
Lemmas referenced : 
rabs-as-rmax, 
rneq-zero, 
rmax-positive, 
rminus_wf, 
rneq_wf, 
int-to-real_wf, 
real_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
sqequalTransitivity, 
computationStep, 
isectElimination, 
thin, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
hypothesis, 
lambdaFormation, 
dependent_functionElimination, 
hypothesisEquality, 
productElimination, 
independent_functionElimination, 
because_Cache, 
natural_numberEquality
Latex:
\mforall{}x:\mBbbR{}.  (x  \mneq{}  r0  {}\mRightarrow{}  rpositive(|x|))
Date html generated:
2016_05_18-AM-07_12_50
Last ObjectModification:
2015_12_28-AM-00_40_59
Theory : reals
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