Metamath Proof Explorer


Theorem ubioc1

Description: The upper bound belongs to an open-below, closed-above interval. See ubicc2 . (Contributed by FL, 29-May-2014)

Ref Expression
Assertion ubioc1 A*B*A<BBAB

Proof

Step Hyp Ref Expression
1 simp2 A*B*A<BB*
2 simp3 A*B*A<BA<B
3 xrleid B*BB
4 3 3ad2ant2 A*B*A<BBB
5 elioc1 A*B*BABB*A<BBB
6 5 3adant3 A*B*A<BBABB*A<BBB
7 1 2 4 6 mpbir3and A*B*A<BBAB