Metamath Proof Explorer


Theorem genpnmax

Description: An operation on positive reals has no largest member. (Contributed by NM, 10-Mar-1996) (Revised by Mario Carneiro, 12-Jun-2013) (New usage is discouraged.)

Ref Expression
Hypotheses genp.1 𝐹 = ( 𝑤P , 𝑣P ↦ { 𝑥 ∣ ∃ 𝑦𝑤𝑧𝑣 𝑥 = ( 𝑦 𝐺 𝑧 ) } )
genp.2 ( ( 𝑦Q𝑧Q ) → ( 𝑦 𝐺 𝑧 ) ∈ Q )
genpnmax.2 ( 𝑣Q → ( 𝑧 <Q 𝑤 ↔ ( 𝑣 𝐺 𝑧 ) <Q ( 𝑣 𝐺 𝑤 ) ) )
genpnmax.3 ( 𝑧 𝐺 𝑤 ) = ( 𝑤 𝐺 𝑧 )
Assertion genpnmax ( ( 𝐴P𝐵P ) → ( 𝑓 ∈ ( 𝐴 𝐹 𝐵 ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) 𝑓 <Q 𝑥 ) )

Proof

Step Hyp Ref Expression
1 genp.1 𝐹 = ( 𝑤P , 𝑣P ↦ { 𝑥 ∣ ∃ 𝑦𝑤𝑧𝑣 𝑥 = ( 𝑦 𝐺 𝑧 ) } )
2 genp.2 ( ( 𝑦Q𝑧Q ) → ( 𝑦 𝐺 𝑧 ) ∈ Q )
3 genpnmax.2 ( 𝑣Q → ( 𝑧 <Q 𝑤 ↔ ( 𝑣 𝐺 𝑧 ) <Q ( 𝑣 𝐺 𝑤 ) ) )
4 genpnmax.3 ( 𝑧 𝐺 𝑤 ) = ( 𝑤 𝐺 𝑧 )
5 1 2 genpelv ( ( 𝐴P𝐵P ) → ( 𝑓 ∈ ( 𝐴 𝐹 𝐵 ) ↔ ∃ 𝑔𝐴𝐵 𝑓 = ( 𝑔 𝐺 ) ) )
6 prnmax ( ( 𝐴P𝑔𝐴 ) → ∃ 𝑦𝐴 𝑔 <Q 𝑦 )
7 6 adantr ( ( ( 𝐴P𝑔𝐴 ) ∧ ( 𝐵P𝐵 ) ) → ∃ 𝑦𝐴 𝑔 <Q 𝑦 )
8 1 2 genpprecl ( ( 𝐴P𝐵P ) → ( ( 𝑦𝐴𝐵 ) → ( 𝑦 𝐺 ) ∈ ( 𝐴 𝐹 𝐵 ) ) )
9 8 exp4b ( 𝐴P → ( 𝐵P → ( 𝑦𝐴 → ( 𝐵 → ( 𝑦 𝐺 ) ∈ ( 𝐴 𝐹 𝐵 ) ) ) ) )
10 9 com34 ( 𝐴P → ( 𝐵P → ( 𝐵 → ( 𝑦𝐴 → ( 𝑦 𝐺 ) ∈ ( 𝐴 𝐹 𝐵 ) ) ) ) )
11 10 imp32 ( ( 𝐴P ∧ ( 𝐵P𝐵 ) ) → ( 𝑦𝐴 → ( 𝑦 𝐺 ) ∈ ( 𝐴 𝐹 𝐵 ) ) )
12 elprnq ( ( 𝐵P𝐵 ) → Q )
13 vex 𝑔 ∈ V
14 vex 𝑦 ∈ V
15 vex ∈ V
16 13 14 3 15 4 caovord2 ( Q → ( 𝑔 <Q 𝑦 ↔ ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) )
17 16 biimpd ( Q → ( 𝑔 <Q 𝑦 → ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) )
18 12 17 syl ( ( 𝐵P𝐵 ) → ( 𝑔 <Q 𝑦 → ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) )
19 18 adantl ( ( 𝐴P ∧ ( 𝐵P𝐵 ) ) → ( 𝑔 <Q 𝑦 → ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) )
20 11 19 anim12d ( ( 𝐴P ∧ ( 𝐵P𝐵 ) ) → ( ( 𝑦𝐴𝑔 <Q 𝑦 ) → ( ( 𝑦 𝐺 ) ∈ ( 𝐴 𝐹 𝐵 ) ∧ ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) ) )
21 breq2 ( 𝑥 = ( 𝑦 𝐺 ) → ( ( 𝑔 𝐺 ) <Q 𝑥 ↔ ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) )
22 21 rspcev ( ( ( 𝑦 𝐺 ) ∈ ( 𝐴 𝐹 𝐵 ) ∧ ( 𝑔 𝐺 ) <Q ( 𝑦 𝐺 ) ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 )
23 20 22 syl6 ( ( 𝐴P ∧ ( 𝐵P𝐵 ) ) → ( ( 𝑦𝐴𝑔 <Q 𝑦 ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 ) )
24 23 adantlr ( ( ( 𝐴P𝑔𝐴 ) ∧ ( 𝐵P𝐵 ) ) → ( ( 𝑦𝐴𝑔 <Q 𝑦 ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 ) )
25 24 expd ( ( ( 𝐴P𝑔𝐴 ) ∧ ( 𝐵P𝐵 ) ) → ( 𝑦𝐴 → ( 𝑔 <Q 𝑦 → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 ) ) )
26 25 rexlimdv ( ( ( 𝐴P𝑔𝐴 ) ∧ ( 𝐵P𝐵 ) ) → ( ∃ 𝑦𝐴 𝑔 <Q 𝑦 → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 ) )
27 7 26 mpd ( ( ( 𝐴P𝑔𝐴 ) ∧ ( 𝐵P𝐵 ) ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 )
28 27 an4s ( ( ( 𝐴P𝐵P ) ∧ ( 𝑔𝐴𝐵 ) ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 )
29 breq1 ( 𝑓 = ( 𝑔 𝐺 ) → ( 𝑓 <Q 𝑥 ↔ ( 𝑔 𝐺 ) <Q 𝑥 ) )
30 29 rexbidv ( 𝑓 = ( 𝑔 𝐺 ) → ( ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) 𝑓 <Q 𝑥 ↔ ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) ( 𝑔 𝐺 ) <Q 𝑥 ) )
31 28 30 syl5ibr ( 𝑓 = ( 𝑔 𝐺 ) → ( ( ( 𝐴P𝐵P ) ∧ ( 𝑔𝐴𝐵 ) ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) 𝑓 <Q 𝑥 ) )
32 31 expdcom ( ( 𝐴P𝐵P ) → ( ( 𝑔𝐴𝐵 ) → ( 𝑓 = ( 𝑔 𝐺 ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) 𝑓 <Q 𝑥 ) ) )
33 32 rexlimdvv ( ( 𝐴P𝐵P ) → ( ∃ 𝑔𝐴𝐵 𝑓 = ( 𝑔 𝐺 ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) 𝑓 <Q 𝑥 ) )
34 5 33 sylbid ( ( 𝐴P𝐵P ) → ( 𝑓 ∈ ( 𝐴 𝐹 𝐵 ) → ∃ 𝑥 ∈ ( 𝐴 𝐹 𝐵 ) 𝑓 <Q 𝑥 ) )