Theorem leltadd 8407

Description: Adding both sides of two orderings. (Contributed by NM, 15-Aug-2008.)

Assertion

Ref	Expression
leltadd	|- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A <_ C /\ B < D ) -> ( A + B ) < ( C + D ) ) )

Proof of Theorem leltadd

Step	Hyp	Ref	Expression
1		ltleadd 8406	. . . . 5 |- ( ( ( B e. RR /\ A e. RR ) /\ ( D e. RR /\ C e. RR ) ) -> ( ( B < D /\ A <_ C ) -> ( B + A ) < ( D + C ) ) )
2	1	ancomsd 269	. . . 4 |- ( ( ( B e. RR /\ A e. RR ) /\ ( D e. RR /\ C e. RR ) ) -> ( ( A <_ C /\ B < D ) -> ( B + A ) < ( D + C ) ) )
3	2	ancom2s 566	. . 3 |- ( ( ( B e. RR /\ A e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A <_ C /\ B < D ) -> ( B + A ) < ( D + C ) ) )
4	3	ancom1s 569	. 2 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A <_ C /\ B < D ) -> ( B + A ) < ( D + C ) ) )
5		recn 7947	. . . 4 |- ( A e. RR -> A e. CC )
6		recn 7947	. . . 4 |- ( B e. RR -> B e. CC )
7		addcom 8097	. . . 4 |- ( ( A e. CC /\ B e. CC ) -> ( A + B ) = ( B + A ) )
8	5, 6, 7	syl2an 289	. . 3 |- ( ( A e. RR /\ B e. RR ) -> ( A + B ) = ( B + A ) )
9		recn 7947	. . . 4 |- ( C e. RR -> C e. CC )
10		recn 7947	. . . 4 |- ( D e. RR -> D e. CC )
11		addcom 8097	. . . 4 |- ( ( C e. CC /\ D e. CC ) -> ( C + D ) = ( D + C ) )
12	9, 10, 11	syl2an 289	. . 3 |- ( ( C e. RR /\ D e. RR ) -> ( C + D ) = ( D + C ) )
13	8, 12	breqan12d 4021	. 2 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A + B ) < ( C + D ) <-> ( B + A ) < ( D + C ) ) )
14	4, 13	sylibrd 169	1 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A <_ C /\ B < D ) -> ( A + B ) < ( C + D ) ) )

Syntax hints:   -> wi 4   /\ wa 104   = wceq 1353   e. wcel 2148   class class class wbr 4005  (class class class)co 5878   CCcc 7812   RRcr 7813   + caddc 7817   < clt 7995   <_ cle 7996

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-13 2150  ax-14 2151  ax-ext 2159  ax-sep 4123  ax-pow 4176  ax-pr 4211  ax-un 4435  ax-setind 4538  ax-cnex 7905  ax-resscn 7906  ax-1cn 7907  ax-icn 7909  ax-addcl 7910  ax-addrcl 7911  ax-mulcl 7912  ax-addcom 7914  ax-addass 7916  ax-i2m1 7919  ax-0id 7922  ax-rnegex 7923  ax-pre-ltwlin 7927  ax-pre-ltadd 7930

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-fal 1359  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ne 2348  df-nel 2443  df-ral 2460  df-rex 2461  df-rab 2464  df-v 2741  df-dif 3133  df-un 3135  df-in 3137  df-ss 3144  df-pw 3579  df-sn 3600  df-pr 3601  df-op 3603  df-uni 3812  df-br 4006  df-opab 4067  df-xp 4634  df-cnv 4636  df-iota 5180  df-fv 5226  df-ov 5881  df-pnf 7997  df-mnf 7998  df-xr 7999  df-ltxr 8000  df-le 8001

This theorem is referenced by:  addgegt0  8409  leltaddd  8526