Theorem psseq2d 4089

Description: An equality deduction for the proper subclass relationship. (Contributed by NM, 9-Jun-2004.)

Hypothesis

Ref	Expression
psseq1d.1	⊢ (𝜑 → 𝐴 = 𝐵)

Assertion

Ref	Expression
psseq2d	⊢ (𝜑 → (𝐶 ⊊ 𝐴 ↔ 𝐶 ⊊ 𝐵))

Proof of Theorem psseq2d

Step	Hyp	Ref	Expression
1		psseq1d.1	. 2 ⊢ (𝜑 → 𝐴 = 𝐵)
2		psseq2 4084	. 2 ⊢ (𝐴 = 𝐵 → (𝐶 ⊊ 𝐴 ↔ 𝐶 ⊊ 𝐵))
3	1, 2	syl 17	1 ⊢ (𝜑 → (𝐶 ⊊ 𝐴 ↔ 𝐶 ⊊ 𝐵))

Syntax hints:   → wi 4   ↔ wb 205   = wceq 1533   ⊊ wpss 3945

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1905  ax-6 1963  ax-7 2003  ax-9 2108  ax-ext 2696

This theorem depends on definitions:  df-bi 206  df-an 395  df-ex 1774  df-cleq 2717  df-ne 2930  df-ss 3961  df-pss 3964

This theorem is referenced by:  psseq12d  4090  php3  9237  php3OLD  9249  inf3lem5  9657  infeq5i  9661  ackbij1lem15  10259  fin4en1  10334  chpsscon1  31386  chnle  31396  atcvatlem  32267  atcvati  32268  lsatcvat  38652