theorem
proved
idAutomorphism_comp_left_toFun
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IndisputableMonolith.RecogGeom.Symmetry on GitHub at line 206.
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All declarations in this module, on Recognition.
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203 simp only [compAutomorphism, Function.comp_assoc]
204
205/-- Identity is left neutral for automorphisms (on toFun) -/
206theorem idAutomorphism_comp_left_toFun (T : RecognitionAutomorphism r) :
207 (compAutomorphism idAutomorphism T).toFun = T.toFun := by
208 simp only [compAutomorphism, idAutomorphism, Function.id_comp]
209
210/-- Identity is right neutral for automorphisms (on toFun) -/
211theorem idAutomorphism_comp_right_toFun (T : RecognitionAutomorphism r) :
212 (compAutomorphism T idAutomorphism).toFun = T.toFun := by
213 simp only [compAutomorphism, idAutomorphism, Function.comp_id]
214
215/-- Right inverse property (on toFun) -/
216theorem compAutomorphism_inv_right_toFun (T : RecognitionAutomorphism r) (c : C) :
217 (compAutomorphism T T.inv).toFun c = c := by
218 simp only [compAutomorphism, RecognitionAutomorphism.inv, Function.comp_apply]
219 exact T.right_inv c
220
221/-- Left inverse property (on toFun) -/
222theorem compAutomorphism_inv_left_toFun (T : RecognitionAutomorphism r) (c : C) :
223 (compAutomorphism T.inv T).toFun c = c := by
224 simp only [compAutomorphism, RecognitionAutomorphism.inv, Function.comp_apply]
225 exact T.left_inv c
226
227/-- The composition T ∘ T⁻¹ acts as identity -/
228theorem compAutomorphism_inv_right_eq_id (T : RecognitionAutomorphism r) :
229 (compAutomorphism T T.inv).toFun = id := by
230 ext c
231 exact compAutomorphism_inv_right_toFun T c
232
233/-- The composition T⁻¹ ∘ T acts as identity -/
234theorem compAutomorphism_inv_left_eq_id (T : RecognitionAutomorphism r) :
235 (compAutomorphism T.inv T).toFun = id := by
236 ext c