Metamath Proof Explorer


Theorem elelpwi

Description: If A belongs to a part of C , then A belongs to C . (Contributed by FL, 3-Aug-2009)

Ref Expression
Assertion elelpwi ( ( 𝐴 ∈ 𝐵 ∧ 𝐵 ∈ 𝒫 𝐶 ) → 𝐴 ∈ 𝐶 )

Proof

Step Hyp Ref Expression
1 elpwi ⊢ ( 𝐵 ∈ 𝒫 𝐶 → 𝐵 ⊆ 𝐶 )
2 1 sseld ⊢ ( 𝐵 ∈ 𝒫 𝐶 → ( 𝐴 ∈ 𝐵 → 𝐴 ∈ 𝐶 ) )
3 2 impcom ⊢ ( ( 𝐴 ∈ 𝐵 ∧ 𝐵 ∈ 𝒫 𝐶 ) → 𝐴 ∈ 𝐶 )