Theorem subnfr-P6.VR 756

Description: Variable Restricted Form of subnfr-P6 755.

'𝑥' cannot occur in '𝛾'.

Hypothesis

Ref	Expression
subnfr-P6.VR.1	⊢ (𝛾 → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
subnfr-P6.VR	⊢ (𝛾 → (Ⅎ𝑥𝜑 ↔ Ⅎ𝑥𝜓))

Distinct variable group:   𝛾,𝑥

Proof of Theorem subnfr-P6.VR

Step	Hyp	Ref	Expression
1		nfrv-P6 686	. 2 ⊢ Ⅎ𝑥𝛾
2		subnfr-P6.VR.1	. 2 ⊢ (𝛾 → (𝜑 ↔ 𝜓))
3	1, 2	subnfr-P6 755	1 ⊢ (𝛾 → (Ⅎ𝑥𝜑 ↔ Ⅎ𝑥𝜓))

Syntax hints:   → wff-imp 10   ↔ wff-bi 104  Ⅎwff-nfree 681

This theorem was proved from axioms:  ax-L1 11  ax-L2 12  ax-L3 13  ax-MP 14  ax-GEN 15  ax-L4 16  ax-L5 17  ax-L6 18  ax-L7 19  ax-L12 29

This theorem depends on definitions:  df-bi-D2.1 107  df-and-D2.2 133  df-or-D2.3 145  df-true-D2.4 155  df-rcp-AND3 161  df-exists-D5.1 596  df-nfree-D6.1 682

This theorem is referenced by:  nfrterm-P6  779