Theorem difeq2i 3270

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 3267	. 2 ⊢ (𝐴 = 𝐵 → (𝐶 ∖ 𝐴) = (𝐶 ∖ 𝐵))
3	1, 2	ax-mp 5	1 ⊢ (𝐶 ∖ 𝐴) = (𝐶 ∖ 𝐵)

Syntax hints:   = wceq 1364   ∖ cdif 3146

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 615  ax-in2 616  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-11 1517  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2171

This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2176  df-cleq 2182  df-clel 2185  df-ral 2473  df-rab 2477  df-dif 3151

This theorem is referenced by:  difeq12i  3271  inssddif  3396  difdif2ss  3412  dif32  3418  difabs  3419  symdif1  3420  notrab  3432  dif0  3513  difdifdirss  3527  dfif3  3566  difpr  3756  dif1o  6478  unfiin  6969