Metamath Proof Explorer


Theorem qseq2d

Description: Equality theorem for quotient set, deduction form. (Contributed by Peter Mazsa, 27-May-2021)

Ref Expression
Hypothesis qseq1d.1 ⊢ ( 𝜑 → 𝐴 = 𝐵 )
Assertion qseq2d ( 𝜑 → ( 𝐶 / 𝐴 ) = ( 𝐶 / 𝐵 ) )

Proof

Step Hyp Ref Expression
1 qseq1d.1 ⊢ ( 𝜑 → 𝐴 = 𝐵 )
2 qseq2 ⊢ ( 𝐴 = 𝐵 → ( 𝐶 / 𝐴 ) = ( 𝐶 / 𝐵 ) )
3 1 2 syl ⊢ ( 𝜑 → ( 𝐶 / 𝐴 ) = ( 𝐶 / 𝐵 ) )