Theorem difeq12i 3619

Description: Equality inference for class difference. (Contributed by NM, 29-Aug-2004.)

Hypotheses

Ref	Expression
difeq1i.1
difeq12i.2

Assertion

Ref	Expression
difeq12i

Proof of Theorem difeq12i

Step	Hyp	Ref	Expression
1		difeq1i.1	. . 3
2	1	difeq1i 3617	. 2
3		difeq12i.2	. . 3
4	3	difeq2i 3618	. 2
5	2, 4	eqtri 2486	1

Syntax hints:  =wceq 1395  \cdif 3472

This theorem is referenced by:  difrab  3771  uniioombllem4  21995  zrdivrng  25434  gtiso  27519  mthmpps  28942  preddif  29271  dvtanlem  30064  isdrngo1  30359  pwfi2f1o  31044

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1618  ax-4 1631  ax-5 1704  ax-6 1747  ax-7 1790  ax-10 1837  ax-11 1842  ax-12 1854  ax-13 1999  ax-ext 2435

This theorem depends on definitions:  df-bi 185  df-an 371  df-tru 1398  df-ex 1613  df-nf 1617  df-sb 1740  df-clab 2443  df-cleq 2449  df-clel 2452  df-nfc 2607  df-ral 2812  df-rab 2816  df-dif 3478