Proof of Theorem glbfval
| Step | Hyp | Ref
| Expression |
| 1 | | elisset 2299 |
. 2

  |
| 2 | | fveq2 4681 |
. . . . . . 7
 base  base    |
| 3 | | glbfval.b |
. . . . . . 7
base   |
| 4 | 2, 3 | syl6eqr 1946 |
. . . . . 6
 base    |
| 5 | | pweq 3036 |
. . . . . 6
 base   base     |
| 6 | 4, 5 | syl 12 |
. . . . 5
  base     |
| 7 | | fveq2 4681 |
. . . . . . . . . 10
 geNEW  geNEW    |
| 8 | | glbfval.l |
. . . . . . . . . 10
geNEW   |
| 9 | 7, 8 | syl6eqr 1946 |
. . . . . . . . 9
 geNEW    |
| 10 | 9 | breqd 3349 |
. . . . . . . 8
   geNEW        |
| 11 | 10 | ralbidv 2123 |
. . . . . . 7
    geNEW         |
| 12 | 9 | breqd 3349 |
. . . . . . . . . 10
   geNEW        |
| 13 | 12 | ralbidv 2123 |
. . . . . . . . 9
    geNEW         |
| 14 | 9 | breqd 3349 |
. . . . . . . . 9
   geNEW        |
| 15 | 13, 14 | imbi12d 688 |
. . . . . . . 8
     geNEW    geNEW              |
| 16 | 4, 15 | raleqbidv 2274 |
. . . . . . 7
   base      geNEW    geNEW               |
| 17 | 11, 16 | anbi12d 690 |
. . . . . 6
     geNEW    base      geNEW    geNEW                     |
| 18 | 4, 17 | riotaeqbidv 5563 |
. . . . 5
   base      geNEW    base      geNEW    geNEW             
 
         |
| 19 | 6, 18 | mpteq12dv 5008 |
. . . 4
   base    base      geNEW   
base      geNEW    geNEW                
 
          |
| 20 | | df-glb 16800 |
. . . 4
glb    base    base      geNEW   
base      geNEW    geNEW         |
| 21 | | fvex 4689 |
. . . . . . 7
base   |
| 22 | 3, 21 | eqeltri 1967 |
. . . . . 6
 |
| 23 | 22 | pwex 3487 |
. . . . 5
  |
| 24 | | mptexg 5012 |
. . . . 5
 
         
 
          |
| 25 | 23, 24 | ax-mp 7 |
. . . 4
         
 
         |
| 26 | 19, 20, 25 | fvmpt 5015 |
. . 3

glb           
 
          |
| 27 | | glbfval.g |
. . 3
glb   |
| 28 | 26, 27 | syl5eq 1940 |
. 2

                      |
| 29 | 1, 28 | syl 12 |
1

                      |