Question

Tính nhanh :

1/2+1/4+1/8+1/16+1/32+1/64

Answer 1

\(2A=1+\dfrac{1}{2}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}\)

\(2A-A=\left(1+\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{18}+\dfrac{1}{32}\right)-\left(\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{64}\right)\)

\(A=1-\dfrac{1}{64}\)

\(A=\dfrac{63}{64}\)

Answer 2

giúp em với ạ , em cấn gấp ,  4h em học rồi ạ . Cảm ơn những ai giúp em ạ , em tick luôn ạ

Answer 3

= 63/64 nha

Answer 4

\(\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{64}=\)\(1-\dfrac{1}{64}\)\(=\dfrac{63}{64}\)

 

 

Answer 5

Đặt\(A=\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{64}\)

\(\dfrac{1}{2}=1-\dfrac{1}{2}\)

\(\Rightarrow\dfrac{1}{2}+\dfrac{1}{4}=\dfrac{3}{4}=1-\dfrac{1}{4}\)

\(\Rightarrow\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}=\dfrac{7}{8}=1-\dfrac{1}{8}\)

\(\Rightarrow A=\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{64}=1-\dfrac{1}{64}\)

\(\Rightarrow A=\dfrac{63}{64}\)

Answer 6

em rất cảm ơn ạ

Answer 7

Ko biết 

 

Answer 8

63/64