This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: The power set of a set is equinumerous to set exponentiation with a base of ordinal 2. Proposition 10.44 of TakeutiZaring p. 96. This is Metamath 100 proof #52. (Contributed by NM, 29-Jan-2004) (Proof shortened by Mario Carneiro, 1-Jul-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | pw2en.1 | ⊢ 𝐴 ∈ V | |
| Assertion | pw2en | ⊢ 𝒫 𝐴 ≈ ( 2o ↑m 𝐴 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | pw2en.1 | ⊢ 𝐴 ∈ V | |
| 2 | pw2eng | ⊢ ( 𝐴 ∈ V → 𝒫 𝐴 ≈ ( 2o ↑m 𝐴 ) ) | |
| 3 | 1 2 | ax-mp | ⊢ 𝒫 𝐴 ≈ ( 2o ↑m 𝐴 ) |