Commit 2021-01-05 20:33 7cf0a29d
View on Github →feat(analysis/normed_space/inner_product): consequences of characterization of orthogonal projection (#5558)
Reverse order of equality in the lemma eq_orthogonal_projection_of_mem_of_inner_eq_zero.  Add some variants.  Also add three consequences:
- the orthogonal projection onto Kof an element ofKis itself
- the orthogonal projection onto Kof an element ofKᗮis zero
- for a submodule Kof an inner product space, the sum of the orthogonal projections ontoKandKᗮis the identity. Reverse order ofiffin the lemmasubmodule.eq_top_iff_orthogonal_eq_bot, and rename tosubmodule.orthogonal_eq_bot_iff.