English
Auxiliary lemma for the symmetric application of preimageHomeomorph.
Русский
Вспомогательная лемма для симметричного применения предобразного гомеоморфизма.
LaTeX
$$$ (preimageHomeomorph_symm_apply.aux e hb) p.2 $$$
Lean4
/-- Composition of a `Trivialization` and a `Homeomorph`. -/
protected def compHomeomorph {Z' : Type*} [TopologicalSpace Z'] (h : Z' ≃ₜ Z) : Trivialization F (proj ∘ h)
where
toOpenPartialHomeomorph := h.toOpenPartialHomeomorph.trans e.toOpenPartialHomeomorph
baseSet := e.baseSet
open_baseSet := e.open_baseSet
source_eq := by simp [source_eq, preimage_preimage, Function.comp_def]
target_eq := by simp [target_eq]
proj_toFun p
hp := by
have hp : h p ∈ e.source := by simpa using hp
simp [hp]