Theorem difeq1d 3340

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

Hypothesis

Ref	Expression
difeq1d.1	⊢ (𝜑 → 𝐴 = 𝐵)

Assertion

Ref	Expression
difeq1d	⊢ (𝜑 → (𝐴 ∖ 𝐶) = (𝐵 ∖ 𝐶))

Proof of Theorem difeq1d

Step	Hyp	Ref	Expression
1		difeq1d.1	. 2 ⊢ (𝜑 → 𝐴 = 𝐵)
2		difeq1 3334	. 2 ⊢ (𝐴 = 𝐵 → (𝐴 ∖ 𝐶) = (𝐵 ∖ 𝐶))
3	1, 2	syl 14	1 ⊢ (𝜑 → (𝐴 ∖ 𝐶) = (𝐵 ∖ 𝐶))

Syntax hints:   → wi 4   = wceq 1398   ∖ cdif 3211

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-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-ext 2216

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-sb 1812  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-rab 2531  df-dif 3216

This theorem is referenced by:  difeq12d  3342  diftpsn3  3840  phplem4  7122  phplem3g  7123  phplem4on  7135  en2other2  7512  ballotfilemfval  13173  ballotfilemfp1  13175  ballotfilemfc0  13176  ballotfilemfcc  13177  ballotfilemgval  13211  ballotfilemgun  13212  isstruct2im  13306  isstruct2r  13307  setsfun0  13332  ptex  13561  cldval  15090  difopn  15099  cnclima  15214