Theorem gte-lteh 50819

Description: Relationship between ≤ and ≥ using hypotheses. (Contributed by David A. Wheeler, 10-May-2015.) (New usage is discouraged.)

Hypotheses

Ref	Expression
gte-lteh.1	⊢ 𝐴 ∈ V
gte-lteh.2	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
gte-lteh	⊢ (𝐴 ≥ 𝐵 ↔ 𝐵 ≤ 𝐴)

Proof of Theorem gte-lteh

Step	Hyp	Ref	Expression
1		df-gte 50815	. . 3 ⊢ ≥ = ◡ ≤
2	1	breqi 5108	. 2 ⊢ (𝐴 ≥ 𝐵 ↔ 𝐴◡ ≤ 𝐵)
3		gte-lteh.1	. . 3 ⊢ 𝐴 ∈ V
4		gte-lteh.2	. . 3 ⊢ 𝐵 ∈ V
5	3, 4	brcnv 5859	. 2 ⊢ (𝐴◡ ≤ 𝐵 ↔ 𝐵 ≤ 𝐴)
6	2, 5	bitri 278	1 ⊢ (𝐴 ≥ 𝐵 ↔ 𝐵 ≤ 𝐴)

This proof depends on syntax axioms:   ↔ wb 209   ∈ wcel 2144  Vcvv 3450   class class class wbr 5102  ^◡ccnv 5649   ≤ cle 11344   ≥ cge-real 50813

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-ext 2732  ax-sep 5248  ax-pr 5390

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-sb 2099  df-clab 2739  df-cleq 2752  df-clel 2835  df-rab 3413  df-v 3452  df-ss 3896  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-if 4482  df-sn 4584  df-pr 4586  df-op 4590  df-br 5103  df-opab 5167  df-cnv 5658  df-gte 50815

This theorem is used by:  ex-gte  50822