Theorem difeq2i 3334

Description: Inference adding difference to the left in a class equality. (Contributed by NM, 15-Nov-2002.)

Hypothesis

Ref	Expression
difeq1i.1	|- A = B

Assertion

Ref	Expression
difeq2i	|- ( C \ A ) = ( C \ B )

Proof of Theorem difeq2i

Step	Hyp	Ref	Expression
1		difeq1i.1	. 2 |- A = B
2		difeq2 3331	. 2 |- ( A = B -> ( C \ A ) = ( C \ B ) )
3	1, 2	ax-mp 5	1 |- ( C \ A ) = ( C \ B )

Syntax hints:   = wceq 1398   \ cdif 3208

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 619  ax-in2 620  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-11 1555  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-ext 2214

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-sb 1812  df-clab 2219  df-cleq 2225  df-clel 2228  df-ral 2525  df-rab 2529  df-dif 3213

This theorem is referenced by:  difeq12i  3335  inssddif  3462  difdif2ss  3478  dif32  3484  difabs  3485  symdif1  3486  notrab  3498  dif0  3579  difdifdirss  3594  dfif3  3636  difpr  3836  dif1o  6671  unfiin  7186  m1bits  12646