Question

tinh a = 1/2 + 1/4 + 1/8 + 1/16 + ... (biet tong tren co 10 so hang)

Answer 1

a=1/2+1/4+1/8+1/16+...+1/1024

=1023/1024

Answer 2

\(\frac{1023}{1024}\)

MÃi mãi có một tương lai tươi sáng

Answer 3

a= 1023 / 1024

Answer 4

=1023/1024

Answer 5

\(a=\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+...\) (a có 10 số hạng)

\(\Rightarrow a=\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+...+\frac{1}{1024}\)

\(\Rightarrow2a=1+\frac{1}{2}+\frac{1}{4}+...+\frac{1}{512}\)

\(\Rightarrow2a-a=\left(1+\frac{1}{2}+\frac{1}{4}+...+\frac{1}{512}\right)-\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+...+\frac{1}{1024}\right)\)

\(\Rightarrow a=1-\frac{1}{1024}\)

\(a=\frac{1023}{1024}\)