Theorem rgen3

Description: Generalization rule for restricted quantification, with three quantifiers. (Contributed by NM, 12-Jan-2008)

	Ref	Expression
Hypothesis	rgen3.1	⊢ ( ( 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) → 𝜑 )
Assertion	rgen3	⊢ ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐵 ∀ 𝑧 ∈ 𝐶 𝜑

Proof

Step	Hyp	Ref	Expression
1		rgen3.1	⊢ ( ( 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) → 𝜑 )
2	1	3expa	⊢ ( ( ( 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) ∧ 𝑧 ∈ 𝐶 ) → 𝜑 )
3	2	ralrimiva	⊢ ( ( 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) → ∀ 𝑧 ∈ 𝐶 𝜑 )
4	3	rgen2	⊢ ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐵 ∀ 𝑧 ∈ 𝐶 𝜑