A = \(\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+....+\frac{1}{2^{100}}\)
2A = \(1+\frac{1}{2}+\frac{1}{2^2}+.....+\frac{1}{2^{99}}\)
A = 2A - A = \(1-\frac{1}{2^{100}}
So sánh : \(A=\frac{1}{2}+\frac{2}{2^2}+\frac{1}{2^3}+...+\frac{1}{2^{100}}với1\)
So sánh : \(A=\frac{1}{2}+\frac{2}{2^2}+\frac{1}{2^3}+...+\frac{1}{2^{100}}với1\)
So sánh:
\(\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+...+\frac{1}{2^{2011}}với1-\frac{1}{2^{2010}}\)
Bài 1: So sánh:
\(\frac{2}{51}+\frac{2}{52}+\frac{2}{53}+.................+\frac{2}{98}+\frac{2}{99}+\frac{2}{100}với1\)
Bài 2: Tìm n thuộc N để mỗi biểu thức sau là STN:
a, \(A=\frac{4}{n-1}+\frac{6}{n-1}-\frac{3}{n-1}\)
b, \(B=\frac{2n+9}{n+2}-\frac{3n}{n+2}+\frac{5n+17}{n+2}\)
1. so sánh
A=\(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+....+với1\)
B=\(1-\left(\frac{1}{5}+\frac{1}{13}+\frac{1}{25}+\frac{1}{41}+\frac{1}{61}+\frac{1}{85}+\frac{1}{113}\right)với\frac{1}{2}\)
C=\(1-\left(\frac{1}{5}+\frac{1}{11}+\frac{1}{10}+\frac{1}{9}+\frac{1}{59}+\frac{1}{58}+\frac{1}{57}\right)với\frac{1}{2}\)
Cho \(S=\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{99^2}+\frac{1}{100^2}\)
So sánh S với 1
1:
a) Cho A= \(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+...+\frac{1}{100^2}\) . So sánh A và \(\frac{199}{100}\)
b) Tìm tích: \(\frac{3}{2^2}.\frac{8}{3^2}.\frac{15}{4^2}.\frac{24}{5^2}.....\frac{99}{10^2}\)
So sánh : \(A=\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{100^2}\) với 2
So sánh A = 1 + \(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{100^2}\) với 2 ta được A ... 2
