Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Sửa: \(A=1+2^1+2^2+2^3+...+2^{2021}\)
\(\Rightarrow A+1=1+1+2+2^2+...+2^{2021}\\ \Rightarrow A+1=2+2+2^2+...+2^{2021}\\ \Rightarrow A+1=2^2+2^2+2^3+...+2^{2021}\\ \Rightarrow A+1=2^3+2^3+2^4+...+2^{2021}\\ ....\\ \Rightarrow A+1=2^{2021}+2^{2021}=2^{2022}\)
Mà \(2^x=A+1\Rightarrow2^x=2^{2022}\Rightarrow x=2022\)
\(A=1+2^1+2^1+2^2+...+2^{2021}\\ \Rightarrow A=1+2+2+2^2+...+2^{2021}\\ \Rightarrow A=1+2.2+2^2+...+2^{2021}\\ \Rightarrow A=1+2^2+2^2+...+2^{2021}\\ \Rightarrow A=1+2.2^2+...+2^{2021}\\ \Rightarrow A=1+2^3+...+2^{2021}\)
....
\(\Rightarrow A=1+2^{2022}\)
\(2^x=1+A\\ \Rightarrow2^x=1+1+2^{2022}\\ \Rightarrow2^x=2+2^{2022}\)
không phù hợp với lớp 6
a) \(A=2+2^2+2^3+...+2^{2022}\)
\(2A=2.\left(2+2^2+2^3+...+2^{2022}\right)\)
\(2.A=2^2+2^3+2^4+...+2^{2023}\)
\(2A-A=\left(2^2+2^3+2^4+...+2^{2023}\right)-\left(2+2^2+2^3+...+2^{2022}\right)\)
\(A=2^{2023}-2\)
b) A + 2 = 2x
Hay \(\left(2^{2023}-2\right)+2=2^x\)
\(2^{2023}-2+2=2^x\)
\(2^{2023}=2^x\)
\(\Rightarrow x=2023\)
a, A = 21 + 22 + 23 + ...+ 22022
2A = 22 + 23 +...+ 22022 + 22023
2A - A = 22023 - 21
A = 22023 - 2
b, A + 2 = 2\(^x\) ⇒ 22023 - 2 + 2 = 2\(x\)
22023 = 2\(^x\)
2023 = \(x\)
