Metamath Proof Explorer


Theorem suprclii

Description: Closure of supremum of a nonempty bounded set of reals. (Contributed by NM, 12-Sep-1999)

Ref Expression
Hypothesis sup3i.1
|- ( A C_ RR /\ A =/= (/) /\ E. x e. RR A. y e. A y <_ x )
Assertion suprclii
|- sup ( A , RR , < ) e. RR

Proof

Step Hyp Ref Expression
1 sup3i.1
 |-  ( A C_ RR /\ A =/= (/) /\ E. x e. RR A. y e. A y <_ x )
2 suprcl
 |-  ( ( A C_ RR /\ A =/= (/) /\ E. x e. RR A. y e. A y <_ x ) -> sup ( A , RR , < ) e. RR )
3 1 2 ax-mp
 |-  sup ( A , RR , < ) e. RR