Nuprl Lemma : rneq-zero-or_wf
∀[x,y:ℝ].  rneq-zero-or(x;y) ∈ x ≠ r0 ∨ y ≠ r0 supposing x ≠ r0 ∨ y ≠ r0
Proof
Definitions occuring in Statement : 
rneq-zero-or: rneq-zero-or(x;y), 
rneq: x ≠ y, 
int-to-real: r(n), 
real: ℝ, 
uimplies: b supposing a, 
uall: ∀[x:A]. B[x], 
or: P ∨ Q, 
member: t ∈ T, 
natural_number: $n
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
or: P ∨ Q, 
prop: ℙ, 
subtype_rel: A ⊆r B, 
all: ∀x:A. B[x], 
sq_stable__rneq-or, 
sq_stable: SqStable(P), 
squash: ↓T, 
implies: P ⇒ Q
Lemmas referenced : 
rneq_wf, 
int-to-real_wf, 
real_wf, 
sq_stable__rneq-or, 
subtype_rel_self, 
sq_stable_wf, 
squash_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
sqequalHypSubstitution, 
hypothesis, 
sqequalRule, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
unionIsType, 
universeIsType, 
extract_by_obid, 
isectElimination, 
thin, 
hypothesisEquality, 
natural_numberEquality, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
inhabitedIsType, 
applyEquality, 
instantiate, 
functionEquality, 
unionEquality, 
imageMemberEquality, 
baseClosed, 
rename, 
functionExtensionality
Latex:
\mforall{}[x,y:\mBbbR{}].    rneq-zero-or(x;y)  \mmember{}  x  \mneq{}  r0  \mvee{}  y  \mneq{}  r0  supposing  x  \mneq{}  r0  \mvee{}  y  \mneq{}  r0
 Date html generated: 
2019_10_29-AM-09_36_22
 Last ObjectModification: 
2019_01_09-PM-05_24_47
Theory : reals
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