Nuprl Lemma : qmul_inv_l
∀[r:ℚ]. (1/r * r) = 1 ∈ ℚ supposing ¬(r = 0 ∈ ℚ)
Proof
Definitions occuring in Statement : 
qinv: 1/r
, 
qmul: 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
, 
squash: ↓T
, 
prop: ℙ
, 
not: ¬A
, 
subtype_rel: A ⊆r B
, 
uiff: uiff(P;Q)
, 
and: P ∧ Q
, 
true: True
, 
guard: {T}
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
implies: P 
⇒ Q
Lemmas referenced : 
equal_wf, 
squash_wf, 
true_wf, 
rationals_wf, 
qmul_com, 
qinv_wf, 
assert-qeq, 
int-subtype-rationals, 
assert_wf, 
qeq_wf2, 
not_wf, 
equal-wf-T-base, 
iff_weakening_equal, 
qmul_inv
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
applyEquality, 
thin, 
lambdaEquality, 
sqequalHypSubstitution, 
imageElimination, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
equalityTransitivity, 
hypothesis, 
equalitySymmetry, 
universeEquality, 
independent_isectElimination, 
addLevel, 
impliesFunctionality, 
because_Cache, 
natural_numberEquality, 
sqequalRule, 
productElimination, 
baseClosed, 
imageMemberEquality, 
independent_functionElimination, 
isect_memberEquality, 
axiomEquality
Latex:
\mforall{}[r:\mBbbQ{}].  (1/r  *  r)  =  1  supposing  \mneg{}(r  =  0)
Date html generated:
2018_05_21-PM-11_49_25
Last ObjectModification:
2017_07_26-PM-06_43_27
Theory : rationals
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