\(A=\frac{\frac{1}{1.300}+\frac{1}{2.301}+...+\frac{1}{101.400}}{\frac{1}{1.102}+\frac{1}{2.103}+...+\frac{1}{299.400}}=\frac{1}{154526}\)
\(A=\frac{\frac{1}{1.300}+\frac{1}{2.301}+...+\frac{1}{101.400}}{\frac{1}{1.102}+\frac{1}{2.103}+...+\frac{1}{299.400}}=\frac{1}{154526}\)
tính
a, A=\(\frac{1}{90}-\frac{1}{72}-\frac{1}{56}-\frac{1}{42}-\frac{1}{30}-\frac{1}{20}-\frac{1}{12}-\frac{1}{6}-\frac{1}{2}\)
b, B=\(\left(\frac{1}{4}-1\right)\left(\frac{1}{9}-1\right)...\left(\frac{1}{100}-1\right)\left(\frac{1}{121}-1\right)\)
c,C=\(\frac{3}{1.4}+\frac{5}{4.9}+\frac{7}{9.16}+\frac{9}{16.25}+\frac{11}{25.36}\)
tính số hữu tỉ \(\frac{A}{B}biết:A=\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...\frac{1}{2007}+\frac{1}{2008}+\frac{1}{2009}B=\frac{2008}{1}+\frac{2007}{1}+\frac{2006}{1}+...+\frac{2}{2007}+\frac{1}{2008}.\)
Cho \(A=\frac{1}{1.2}+\frac{1}{3.4}+\frac{1}{5.6}+...+\frac{1}{9.10}\) và \(B=\frac{1}{6.10}+\frac{1}{7.9}+\frac{1}{8.8}+\frac{1}{9.7}+\frac{1}{10.6}\). Tính A : B
Tính :
\(A=\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{2011}}{\frac{2010}{1}+\frac{2009}{2}+\frac{2008}{3}+...+\frac{1}{2010}}\)
Tính :
\(A=\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{2013}}{\frac{2012}{1}+\frac{2011}{2}+\frac{2010}{3}+...+\frac{1}{2012}}\)
a ) Tính B = \(\frac{1}{2^{2016}}-\left(\frac{1}{2^{2015}}+\frac{1}{2^{2014}}+...+\frac{1}{2^1}+\frac{1}{2^0}\right)\)
b ) Tìm x biết : | x + 1 | + | x + 4 | = 3x
Tính nhanh:
a) A=\(\frac{1}{3}-\frac{3}{4}-\left(-\frac{3}{5}\right)+\frac{1}{72}-\frac{2}{9}-\frac{1}{36}+\frac{2}{15}\)b) B=\(\frac{1}{5}-\frac{3}{7}+\frac{5}{9}-\frac{2}{11}+\frac{7}{13}-\frac{9}{16}-\frac{7}{13}+\frac{2}{11}-\frac{5}{9}+\frac{3}{7}-\frac{1}{5}\)c) C= \(\frac{1}{100}-\frac{1}{100.99}-\frac{1}{99.98}-...-\frac{1}{3.2}-\frac{1}{2.1}\)Cho A=\(\frac{1}{1.2}+\frac{1}{3.4}+...+\frac{1}{2005.2006}\)
B=\(\frac{1}{1004.2006}+\frac{1}{1005.2006}+\frac{1}{1006.2006}+...+\frac{1}{2006.2006}\)
Tính A chia B
Tính giá trị biểu thức:
\(A=\frac{0,125-\frac{1}{5}+\frac{1}{7}}{0,375-\frac{3}{5}+\frac{3}{7}}+\frac{\frac{1}{2}+\frac{1}{3}-0,2}{\frac{3}{4}+0,5-\frac{3}{10}}\)