Nuprl Lemma : inv_funs_sym
∀[A,B:Type]. ∀[f:A ⟶ B]. ∀[g:B ⟶ A].  InvFuns(B;A;g;f) supposing InvFuns(A;B;f;g)
Proof
Definitions occuring in Statement : 
inv_funs: InvFuns(A;B;f;g)
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
inv_funs: InvFuns(A;B;f;g)
, 
and: P ∧ Q
, 
cand: A c∧ B
, 
prop: ℙ
Lemmas referenced : 
inv_funs_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :isect_memberFormation_alt, 
introduction, 
cut, 
sqequalHypSubstitution, 
productElimination, 
thin, 
hypothesis, 
independent_pairFormation, 
sqequalRule, 
independent_pairEquality, 
axiomEquality, 
Error :universeIsType, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
isect_memberEquality, 
equalityTransitivity, 
equalitySymmetry, 
Error :functionIsType, 
because_Cache, 
functionEquality, 
Error :inhabitedIsType, 
universeEquality
Latex:
\mforall{}[A,B:Type].  \mforall{}[f:A  {}\mrightarrow{}  B].  \mforall{}[g:B  {}\mrightarrow{}  A].    InvFuns(B;A;g;f)  supposing  InvFuns(A;B;f;g)
Date html generated:
2019_06_20-PM-00_26_30
Last ObjectModification:
2018_09_26-PM-00_09_28
Theory : fun_1
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