Câu hỏi của Nông Mạnh Dũng

Question

Tìm tổng: S=1+2+2^2+2^3+2^4+2^5+............+2^49+2^50

Mai Nhật Lệ · Accepted Answer

$S=1+2+2^2+...+2^{50}$

$2S=2.1+2.2+2^2.2+...+2^{50}.2$

$2S=2+2^2+2^3+...+2^{51}$

$2S-S=S=\left(2+2^2+2^3+...+2^{51}\right)-\left(1+2+2^2+...+2^{50}\right)$

$\Rightarrow S=2^{51}-1$

Câu trả lời:

$S=1+2+2^2+...+2^{50}$

$2S=2.1+2.2+2^2.2+...+2^{50}.2$

$2S=2+2^2+2^3+...+2^{51}$

$2S-S=S=\left(2+2^2+2^3+...+2^{51}\right)-\left(1+2+2^2+...+2^{50}\right)$

$\Rightarrow S=2^{51}-1$

Hồng Nguyễn Thị · Answer

2S - S = ( 2+2^2 + 2^3 +....+ 2^51 ) - (1+2+2^2+...+2^50)
S= 1 + 2^51
Vậy nha

Câu trả lời:

2S - S = ( 2+2^2 + 2^3 +....+ 2^51 ) - (1+2+2^2+...+2^50)
S= 1 + 2^51
Vậy nha