Đặt \(S=\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+\frac{1}{2^4}+...+\frac{1}{2^{10}}\)
\(2S=1+\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+...+\frac{1}{2^9}\)
\(2S-S=1-\frac{1}{2^{10}}\)
\(S=\frac{1024}{1024}-\frac{1}{1024}=\frac{1023}{1024}\)
Vậy \(S=\frac{1023}{1024}\)
P.S: Bạn để \(S=1-\frac{1}{2^{10}}\)vẫn được.