`BookProof.ReducedEsa.symProj_mem` (hUD : ∀ x ∈ D, U x ∈ D) : ∀ x ∈ D, symProj U x ∈ D

Initializing...

`BookProof.ReducedEsa.symProj_mem` (hUD : ∀ x ∈ D, U x ∈ D) : ∀ x ∈ D, symProj U x ∈ D · Prove2Me