Theorem freq12d

Description: Equality deduction for founded relations. (Contributed by Stefan O'Rear, 19-Jan-2015)

	Ref	Expression
Hypotheses	weeq12d.l	⊢ ( 𝜑 → 𝑅 = 𝑆 )
	weeq12d.r	⊢ ( 𝜑 → 𝐴 = 𝐵 )
Assertion	freq12d	⊢ ( 𝜑 → ( 𝑅 Fr 𝐴 ↔ 𝑆 Fr 𝐵 ) )

Proof

Step	Hyp	Ref	Expression
1		weeq12d.l	⊢ ( 𝜑 → 𝑅 = 𝑆 )
2		weeq12d.r	⊢ ( 𝜑 → 𝐴 = 𝐵 )
3		freq1	⊢ ( 𝑅 = 𝑆 → ( 𝑅 Fr 𝐴 ↔ 𝑆 Fr 𝐴 ) )
4	1 3	syl	⊢ ( 𝜑 → ( 𝑅 Fr 𝐴 ↔ 𝑆 Fr 𝐴 ) )
5		freq2	⊢ ( 𝐴 = 𝐵 → ( 𝑆 Fr 𝐴 ↔ 𝑆 Fr 𝐵 ) )
6	2 5	syl	⊢ ( 𝜑 → ( 𝑆 Fr 𝐴 ↔ 𝑆 Fr 𝐵 ) )
7	4 6	bitrd	⊢ ( 𝜑 → ( 𝑅 Fr 𝐴 ↔ 𝑆 Fr 𝐵 ) )