\(B=\dfrac{1}{2}+\dfrac{1}{2^2}+\dfrac{1}{2^3}+.......+\dfrac{1}{2^{2017}}\)
\(\Leftrightarrow2B=1+\dfrac{1}{2}+\dfrac{1}{2^2}+\dfrac{1}{2^3}+............+\dfrac{1}{2^{2016}}\)
\(\Leftrightarrow2B-B=\left(1+\dfrac{1}{2}+\dfrac{1}{2^2}+..........+\dfrac{1}{2^{2016}}\right)-\left(\dfrac{1}{2}+\dfrac{1}{2^2}+........+\dfrac{1}{2^{2017}}\right)\)
\(\Leftrightarrow B=1-\dfrac{1}{2^{2017}}\)
A=1/2+1/3+1/4+...+1/2019;B=1/2018 +2/2017+3/2016+...+2017/2+2018/1.Tính A/B
so sánh a,b biết: a= 2^2018-3/2^2017-1 và b=2^2017-3/2^2016-1
\(A=\frac{2017}{1+\frac{1}{1+2}+\frac{1}{1+2+3}+...+\frac{1}{1+2+...+2017}}\)
1+1/1+2+1/1+2+3+...+1/1+2+3+..+2017
Tính B=\(\left(1-\dfrac{1}{1+2}\right).\left(1-\dfrac{1}{1+2+3}\right).....\left(1-\dfrac{1}{1+2+3+...+2017}\right)\)
tính B : \(=\left(1-\dfrac{1}{1+2}\right)\left(1-\dfrac{1}{1+2+3}\right)...\left(1-\dfrac{1}{1+2+3+...+2017}\right)\)
tỉ số của 2 số A=(-2)^0 + 1^2017 + (-1/3)^8 . 3^8/2^15 và B=6^2/2^16
Tính: A = (1- 1/2)(1-1/3)(1-1/4)...(1-1/2016)(1-1/2017)
S= 2^2010 - 2^2009 - 2^2008 - ... - 2 - 1
Tính B\(=\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{2017}}{\frac{2016}{1}+\frac{2003}{2}+\frac{2002}{3}+...+\frac{1}{2016}}\)
