Corollary
Tag 01D7, permanent. Cite it as [Bourbaki, Tag 01D7].
Lie Groups and Lie Algebras, chapter IX, § 4. Root system associated to a compact group
Let be a framing of and let E be the group of automorphisms of G that leave stable. Then Aut(G) is the semi-direct product of E by Int(G), and Aut(G) is the semi-direct product of E by Int(G) Aut(G) Int.
Indeed, every element of Aut(G) transforms into a framing of G. By Prop. 19, every coset of Aut(G) modulo Int(G) meets E in a single point, hence the first assertion. The second is proved in the same way.
Bourbaki sets the proof directly after the statement, and the corpus does not separate them, so what is above is the statement and its proof together.
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