Theorem difeq1d 3346

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

Hypothesis

Ref	Expression
difeq1d.1	|- ( ph -> A = B )

Assertion

Ref	Expression
difeq1d	|- ( ph -> ( A \ C ) = ( B \ C ) )

Proof of Theorem difeq1d

Step	Hyp	Ref	Expression
1		difeq1d.1	. 2 |- ( ph -> A = B )
2		difeq1 3340	. 2 |- ( A = B -> ( A \ C ) = ( B \ C ) )
3	1, 2	syl 14	1 |- ( ph -> ( A \ C ) = ( B \ C ) )

This proof depends on syntax axioms:   -> wi 4   = wceq 1402   \ cdif 3217

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This proof depends on definitions:  df-bi 117  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-rab 2537  df-dif 3222

This theorem is used by:  difeq12d  3348  diftpsn3  3856  phplem4  7156  phplem3g  7157  phplem4on  7169  en2other2  7548  ballotfilemfval  13278  ballotfilemfp1  13280  ballotfilemfc0  13281  ballotfilemfcc  13282  ballotfilemgval  13316  ballotfilemgun  13317  isstruct2im  13411  isstruct2r  13412  setsfun0  13437  ptex  13667  cldval  15249  difopn  15258  cnclima  15373