Metamath Proof Explorer
Description: Elementhood to a power set. (Contributed by Thierry Arnoux, 18-May-2020)
|
|
Ref |
Expression |
|
Hypotheses |
sselpwd.1 |
⊢ ( 𝜑 → 𝐵 ∈ 𝑉 ) |
|
|
sselpwd.2 |
⊢ ( 𝜑 → 𝐴 ⊆ 𝐵 ) |
|
Assertion |
sselpwd |
⊢ ( 𝜑 → 𝐴 ∈ 𝒫 𝐵 ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
sselpwd.1 |
⊢ ( 𝜑 → 𝐵 ∈ 𝑉 ) |
2 |
|
sselpwd.2 |
⊢ ( 𝜑 → 𝐴 ⊆ 𝐵 ) |
3 |
1 2
|
ssexd |
⊢ ( 𝜑 → 𝐴 ∈ V ) |
4 |
3 2
|
elpwd |
⊢ ( 𝜑 → 𝐴 ∈ 𝒫 𝐵 ) |