| Step | Hyp | Ref | Expression | 
						
							| 1 |  | simpr |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> C = (/) ) | 
						
							| 2 | 1 | oveq1d |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> ( C ^m A ) = ( (/) ^m A ) ) | 
						
							| 3 |  | simplr |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> -. ( A = (/) /\ C = (/) ) ) | 
						
							| 4 |  | idd |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> ( A = (/) -> A = (/) ) ) | 
						
							| 5 | 4 1 | jctird |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> ( A = (/) -> ( A = (/) /\ C = (/) ) ) ) | 
						
							| 6 | 3 5 | mtod |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> -. A = (/) ) | 
						
							| 7 | 6 | neqned |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> A =/= (/) ) | 
						
							| 8 |  | map0b |  |-  ( A =/= (/) -> ( (/) ^m A ) = (/) ) | 
						
							| 9 | 7 8 | syl |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> ( (/) ^m A ) = (/) ) | 
						
							| 10 | 2 9 | eqtrd |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> ( C ^m A ) = (/) ) | 
						
							| 11 |  | ovex |  |-  ( C ^m B ) e. _V | 
						
							| 12 | 11 | 0dom |  |-  (/) ~<_ ( C ^m B ) | 
						
							| 13 | 10 12 | eqbrtrdi |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C = (/) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 14 |  | simpll |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> A ~<_ B ) | 
						
							| 15 |  | reldom |  |-  Rel ~<_ | 
						
							| 16 | 15 | brrelex2i |  |-  ( A ~<_ B -> B e. _V ) | 
						
							| 17 | 16 | ad2antrr |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> B e. _V ) | 
						
							| 18 |  | domeng |  |-  ( B e. _V -> ( A ~<_ B <-> E. x ( A ~~ x /\ x C_ B ) ) ) | 
						
							| 19 | 17 18 | syl |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> ( A ~<_ B <-> E. x ( A ~~ x /\ x C_ B ) ) ) | 
						
							| 20 | 14 19 | mpbid |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> E. x ( A ~~ x /\ x C_ B ) ) | 
						
							| 21 |  | enrefg |  |-  ( C e. _V -> C ~~ C ) | 
						
							| 22 | 21 | ad2antlr |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> C ~~ C ) | 
						
							| 23 |  | simprrl |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> A ~~ x ) | 
						
							| 24 |  | mapen |  |-  ( ( C ~~ C /\ A ~~ x ) -> ( C ^m A ) ~~ ( C ^m x ) ) | 
						
							| 25 | 22 23 24 | syl2anc |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m A ) ~~ ( C ^m x ) ) | 
						
							| 26 |  | ovexd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m x ) e. _V ) | 
						
							| 27 |  | ovexd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m ( B \ x ) ) e. _V ) | 
						
							| 28 |  | simprl |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> C =/= (/) ) | 
						
							| 29 |  | simplr |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> C e. _V ) | 
						
							| 30 | 16 | ad2antrr |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> B e. _V ) | 
						
							| 31 | 30 | difexd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( B \ x ) e. _V ) | 
						
							| 32 |  | map0g |  |-  ( ( C e. _V /\ ( B \ x ) e. _V ) -> ( ( C ^m ( B \ x ) ) = (/) <-> ( C = (/) /\ ( B \ x ) =/= (/) ) ) ) | 
						
							| 33 |  | simpl |  |-  ( ( C = (/) /\ ( B \ x ) =/= (/) ) -> C = (/) ) | 
						
							| 34 | 32 33 | biimtrdi |  |-  ( ( C e. _V /\ ( B \ x ) e. _V ) -> ( ( C ^m ( B \ x ) ) = (/) -> C = (/) ) ) | 
						
							| 35 | 34 | necon3d |  |-  ( ( C e. _V /\ ( B \ x ) e. _V ) -> ( C =/= (/) -> ( C ^m ( B \ x ) ) =/= (/) ) ) | 
						
							| 36 | 29 31 35 | syl2anc |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C =/= (/) -> ( C ^m ( B \ x ) ) =/= (/) ) ) | 
						
							| 37 | 28 36 | mpd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m ( B \ x ) ) =/= (/) ) | 
						
							| 38 |  | xpdom3 |  |-  ( ( ( C ^m x ) e. _V /\ ( C ^m ( B \ x ) ) e. _V /\ ( C ^m ( B \ x ) ) =/= (/) ) -> ( C ^m x ) ~<_ ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ) | 
						
							| 39 | 26 27 37 38 | syl3anc |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m x ) ~<_ ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ) | 
						
							| 40 |  | vex |  |-  x e. _V | 
						
							| 41 | 40 | a1i |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> x e. _V ) | 
						
							| 42 |  | disjdif |  |-  ( x i^i ( B \ x ) ) = (/) | 
						
							| 43 | 42 | a1i |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( x i^i ( B \ x ) ) = (/) ) | 
						
							| 44 |  | mapunen |  |-  ( ( ( x e. _V /\ ( B \ x ) e. _V /\ C e. _V ) /\ ( x i^i ( B \ x ) ) = (/) ) -> ( C ^m ( x u. ( B \ x ) ) ) ~~ ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ) | 
						
							| 45 | 41 31 29 43 44 | syl31anc |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m ( x u. ( B \ x ) ) ) ~~ ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ) | 
						
							| 46 | 45 | ensymd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ~~ ( C ^m ( x u. ( B \ x ) ) ) ) | 
						
							| 47 |  | simprrr |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> x C_ B ) | 
						
							| 48 |  | undif |  |-  ( x C_ B <-> ( x u. ( B \ x ) ) = B ) | 
						
							| 49 | 47 48 | sylib |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( x u. ( B \ x ) ) = B ) | 
						
							| 50 | 49 | oveq2d |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m ( x u. ( B \ x ) ) ) = ( C ^m B ) ) | 
						
							| 51 | 46 50 | breqtrd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ~~ ( C ^m B ) ) | 
						
							| 52 |  | domentr |  |-  ( ( ( C ^m x ) ~<_ ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) /\ ( ( C ^m x ) X. ( C ^m ( B \ x ) ) ) ~~ ( C ^m B ) ) -> ( C ^m x ) ~<_ ( C ^m B ) ) | 
						
							| 53 | 39 51 52 | syl2anc |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m x ) ~<_ ( C ^m B ) ) | 
						
							| 54 |  | endomtr |  |-  ( ( ( C ^m A ) ~~ ( C ^m x ) /\ ( C ^m x ) ~<_ ( C ^m B ) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 55 | 25 53 54 | syl2anc |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ ( C =/= (/) /\ ( A ~~ x /\ x C_ B ) ) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 56 | 55 | expr |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> ( ( A ~~ x /\ x C_ B ) -> ( C ^m A ) ~<_ ( C ^m B ) ) ) | 
						
							| 57 | 56 | exlimdv |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> ( E. x ( A ~~ x /\ x C_ B ) -> ( C ^m A ) ~<_ ( C ^m B ) ) ) | 
						
							| 58 | 20 57 | mpd |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ C =/= (/) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 59 | 58 | adantlr |  |-  ( ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) /\ C =/= (/) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 60 | 13 59 | pm2.61dane |  |-  ( ( ( A ~<_ B /\ C e. _V ) /\ -. ( A = (/) /\ C = (/) ) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 61 | 60 | an32s |  |-  ( ( ( A ~<_ B /\ -. ( A = (/) /\ C = (/) ) ) /\ C e. _V ) -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 62 | 61 | ex |  |-  ( ( A ~<_ B /\ -. ( A = (/) /\ C = (/) ) ) -> ( C e. _V -> ( C ^m A ) ~<_ ( C ^m B ) ) ) | 
						
							| 63 |  | reldmmap |  |-  Rel dom ^m | 
						
							| 64 | 63 | ovprc1 |  |-  ( -. C e. _V -> ( C ^m A ) = (/) ) | 
						
							| 65 | 64 12 | eqbrtrdi |  |-  ( -. C e. _V -> ( C ^m A ) ~<_ ( C ^m B ) ) | 
						
							| 66 | 62 65 | pm2.61d1 |  |-  ( ( A ~<_ B /\ -. ( A = (/) /\ C = (/) ) ) -> ( C ^m A ) ~<_ ( C ^m B ) ) |