Theorem cnmpt2nd 12458

Description: The projection onto the second coordinate is continuous. (Contributed by Mario Carneiro, 6-May-2014.) (Revised by Mario Carneiro, 22-Aug-2015.)

Hypotheses

Ref	Expression
cnmpt21.j	|- ( ph -> J e. (TopOn ` X ) )
cnmpt21.k	|- ( ph -> K e. (TopOn ` Y ) )

Assertion

Ref	Expression
cnmpt2nd	|- ( ph -> ( x e. X , y e. Y |-> y ) e. ( ( J tX K ) Cn K ) )

Distinct variable groups:   x, y, ph   x, X, y   x, Y, y

Allowed substitution hints:   J( x, y)   K( x, y)

Proof of Theorem cnmpt2nd

Dummy variable z is distinct from all other variables.

Step	Hyp	Ref	Expression
1		fo2nd 6056	. . . . . 6 |- 2nd : _V -onto-> _V
2		fofn 5347	. . . . . 6 |- ( 2nd : _V -onto-> _V -> 2nd Fn _V )
3	1, 2	ax-mp 5	. . . . 5 |- 2nd Fn _V
4		ssv 3119	. . . . 5 |- ( X X. Y ) C_ _V
5		fnssres 5236	. . . . 5 |- ( ( 2nd Fn _V /\ ( X X. Y ) C_ _V ) -> ( 2nd |` ( X X. Y ) ) Fn ( X X. Y ) )
6	3, 4, 5	mp2an 422	. . . 4 |- ( 2nd |` ( X X. Y ) ) Fn ( X X. Y )
7		dffn5im 5467	. . . 4 |- ( ( 2nd |` ( X X. Y ) ) Fn ( X X. Y ) -> ( 2nd |` ( X X. Y ) ) = ( z e. ( X X. Y ) |-> ( ( 2nd |` ( X X. Y ) ) ` z ) ) )
8	6, 7	ax-mp 5	. . 3 |- ( 2nd |` ( X X. Y ) ) = ( z e. ( X X. Y ) |-> ( ( 2nd |` ( X X. Y ) ) ` z ) )
9		fvres 5445	. . . 4 |- ( z e. ( X X. Y ) -> ( ( 2nd |` ( X X. Y ) ) ` z ) = ( 2nd ` z ) )
10	9	mpteq2ia 4014	. . 3 |- ( z e. ( X X. Y ) |-> ( ( 2nd |` ( X X. Y ) ) ` z ) ) = ( z e. ( X X. Y ) |-> ( 2nd ` z ) )
11		vex 2689	. . . . 5 |- x e. _V
12		vex 2689	. . . . 5 |- y e. _V
13	11, 12	op2ndd 6047	. . . 4 |- ( z = <. x , y >. -> ( 2nd ` z ) = y )
14	13	mpompt 5863	. . 3 |- ( z e. ( X X. Y ) |-> ( 2nd ` z ) ) = ( x e. X , y e. Y |-> y )
15	8, 10, 14	3eqtri 2164	. 2 |- ( 2nd |` ( X X. Y ) ) = ( x e. X , y e. Y |-> y )
16		cnmpt21.j	. . 3 |- ( ph -> J e. (TopOn ` X ) )
17		cnmpt21.k	. . 3 |- ( ph -> K e. (TopOn ` Y ) )
18		tx2cn 12439	. . 3 |- ( ( J e. (TopOn ` X ) /\ K e. (TopOn ` Y ) ) -> ( 2nd |` ( X X. Y ) ) e. ( ( J tX K ) Cn K ) )
19	16, 17, 18	syl2anc 408	. 2 |- ( ph -> ( 2nd |` ( X X. Y ) ) e. ( ( J tX K ) Cn K ) )
20	15, 19	eqeltrrid 2227	1 |- ( ph -> ( x e. X , y e. Y |-> y ) e. ( ( J tX K ) Cn K ) )

Syntax hints:   -> wi 4   = wceq 1331   e. wcel 1480   _Vcvv 2686   C_ wss 3071   |-> cmpt 3989   X. cxp 4537   |` cres 4541   Fn wfn 5118   -onto->wfo 5121   ` cfv 5123  (class class class)co 5774   e. cmpo 5776   2ndc2nd 6037  TopOnctopon 12177   Cn ccn 12354   tX ctx 12421

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 603  ax-in2 604  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-13 1491  ax-14 1492  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121  ax-coll 4043  ax-sep 4046  ax-pow 4098  ax-pr 4131  ax-un 4355  ax-setind 4452

This theorem depends on definitions:  df-bi 116  df-3an 964  df-tru 1334  df-fal 1337  df-nf 1437  df-sb 1736  df-eu 2002  df-mo 2003  df-clab 2126  df-cleq 2132  df-clel 2135  df-nfc 2270  df-ne 2309  df-ral 2421  df-rex 2422  df-reu 2423  df-rab 2425  df-v 2688  df-sbc 2910  df-csb 3004  df-dif 3073  df-un 3075  df-in 3077  df-ss 3084  df-pw 3512  df-sn 3533  df-pr 3534  df-op 3536  df-uni 3737  df-iun 3815  df-br 3930  df-opab 3990  df-mpt 3991  df-id 4215  df-xp 4545  df-rel 4546  df-cnv 4547  df-co 4548  df-dm 4549  df-rn 4550  df-res 4551  df-ima 4552  df-iota 5088  df-fun 5125  df-fn 5126  df-f 5127  df-f1 5128  df-fo 5129  df-f1o 5130  df-fv 5131  df-ov 5777  df-oprab 5778  df-mpo 5779  df-1st 6038  df-2nd 6039  df-map 6544  df-topgen 12141  df-top 12165  df-topon 12178  df-bases 12210  df-cn 12357  df-tx 12422

This theorem is referenced by:  cnmptcom  12467  txhmeo  12488  txswaphmeo  12490  divcnap  12724  cnrehmeocntop  12762