Metamath Proof Explorer


Theorem sspwd

Description: The powerclass preserves inclusion (deduction form). (Contributed by BJ, 13-Apr-2024)

Ref Expression
Hypothesis sspwd.1 ⊢ φ → A ⊆ B
Assertion sspwd ⊢ φ → 𝒫 A ⊆ 𝒫 B

Proof

Step Hyp Ref Expression
1 sspwd.1 ⊢ φ → A ⊆ B
2 sspw ⊢ A ⊆ B → 𝒫 A ⊆ 𝒫 B
3 1 2 syl ⊢ φ → 𝒫 A ⊆ 𝒫 B