Question

Cíu mk với :

 

Answer 1

???

Answer 2

sao

Answer 3

Bài 5. a) \(A=1+2+2^2+2^3+...+2^{2021}\)

\(\Rightarrow2A=2+2^2+2^3+2^4+...+2^{2022}\)

\(\Rightarrow A=2A-A=\left(2+2^2+2^3+2^4+...+2^{2022}\right)-\left(1+2+2^2+2^3+...+2^{2021}\right)\)

\(=2^{2022}-1\)

\(\Rightarrow2A=2.\left(2^{2022}-1\right)=2^{2023}-2\)

b) Đề sai, phải là A = 2²⁰²² - 1