Question: why bismillah is not in surah taubah?
Answer: The reason why the Bismillah does not appear at the beginning of Soorat at-Tawbah is that the Sahaabah (may Allah be pleased with them) did not write it at the beginning of this soorah in the Mushaf, following the example of the caliph 'Uthmaan (may Allah be pleased with him).