Theorem difeq2i 3222

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 3219	. 2 ⊢ (𝐴 = 𝐵 → (𝐶 ∖ 𝐴) = (𝐶 ∖ 𝐵))
3	1, 2	ax-mp 5	1 ⊢ (𝐶 ∖ 𝐴) = (𝐶 ∖ 𝐵)

Syntax hints:   = wceq 1335   ∖ cdif 3099

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 604  ax-in2 605  ax-5 1427  ax-7 1428  ax-gen 1429  ax-ie1 1473  ax-ie2 1474  ax-8 1484  ax-11 1486  ax-4 1490  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2139

This theorem depends on definitions:  df-bi 116  df-tru 1338  df-nf 1441  df-sb 1743  df-clab 2144  df-cleq 2150  df-clel 2153  df-ral 2440  df-rab 2444  df-dif 3104

This theorem is referenced by:  difeq12i  3223  inssddif  3348  difdif2ss  3364  dif32  3370  difabs  3371  symdif1  3372  notrab  3384  dif0  3464  difdifdirss  3478  dfif3  3518  difpr  3698  dif1o  6379  unfiin  6863