Tính: a) S=C2022092022+C2022192021+…+C2022k92022−k+…+C202220219+C20222022. b) T=C2022042022−C2022142021 . 3+…−C202220214 . 32021+C2022202232022.
Câu hỏi: Tính: a) S=C2022092022+C2022192021+...+C2022k92022−k+...+C202220219+C20222022. b) T=C2022042022−C2022142021 . 3+...−C202220214 . 32021+C2022202232022. Trả lời: Áp dụng công thức nhị thức Newton ta có: a) S=C2022092022+C2022192021+...+C2022k92022−k+...+C202220219+C20222022 =C2022092022+C2022192021 . 1+...+C2022k92022−k.1k+...+C202220219.12021+C20222022.12022 =9+12020=102022.…