let A be finite Tolerance_Space; for X being Subset of A
for x being Element of A holds
( 0 <= (MemberFunc X,A) . x & (MemberFunc X,A) . x <= 1 )
let X be Subset of A; for x being Element of A holds
( 0 <= (MemberFunc X,A) . x & (MemberFunc X,A) . x <= 1 )
let x be Element of A; ( 0 <= (MemberFunc X,A) . x & (MemberFunc X,A) . x <= 1 )
(card (X /\ (Class the InternalRel of A,x))) / (card (Class the InternalRel of A,x)) >= 0
;
hence
0 <= (MemberFunc X,A) . x
by Def9; (MemberFunc X,A) . x <= 1
card (X /\ (Class the InternalRel of A,x)) <= card (Class the InternalRel of A,x)
by NAT_1:44, XBOOLE_1:17;
then
(card (X /\ (Class the InternalRel of A,x))) / (card (Class the InternalRel of A,x)) <= 1
by XREAL_1:187;
hence
(MemberFunc X,A) . x <= 1
by Def9; verum