Tính\(\left(1-\frac{1}{15}\right)\times\left(1-\frac{1}{21}\right)\times\left(1-\frac{1}{28}\right)\times......\times\left(1-\frac{1}{20}\right)\)
Tính P = \(\left(1+\frac{1}{3}\right)\times\left(1+\frac{1}{2\times4}\right)\times\left(1+\frac{1}{3\times5}\right)\times\left(1+\frac{1}{4\times6}\right)\times...\times\left(1+\frac{1}{2009\times2011}\right)\)
Tính giá trị biểu thức: A=\(\frac{\left(1+17\right)\times\left(1+\frac{17}{2}\right)\times\left(1+\frac{17}{3}\right)....\left(1+\frac{17}{19}\right)}{\left(1+19\right)\times\left(1+\frac{19}{2}\right)\times\left(1+\frac{19}{3}\right)....\left(1+\frac{19}{17}\right)}\)
tính \(A=\frac{1}{2}\times\left(1+\frac{1}{1\times3}\right)\times\left(1+\frac{1}{2\times4}\right)\times\left(1+\frac{1}{3\times5}\right)\times...\times\left(1+\frac{1}{2015\times2017}\right)\)
Tính\(\left(1-\frac{4}{1}\right)\times\left(1-\frac{4}{9}\right)\times\left(1-\frac{1}{25}\right)\times......\times\left(1-\frac{4}{2n-1}\right)\)
Kết quả của phép tính:
\(\left(-2\right)\times\left(-1\frac{1}{2}\right)\times\left(-1\frac{1}{3}\right)..........\times\left(-1\frac{1}{2009}\right)\times\left(-1\frac{1}{2010}\right)\)
Tính :\(B=\left(1-\frac{2}{6}\right)\times\left(1-\frac{2}{12}\right)\times\left(1-\frac{2}{20}\right)\times...\times\left(1-\frac{2}{9900}\right)\)
TÍNH
\(\frac{\left(1+2+3+...+100\right)\times\left(\frac{1}{3}-\frac{1}{5}-\frac{1}{7}-\frac{1}{9}\right)\times\left(6,3\times12-21\times3,6\right)}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{100}}\)
Tính nhanh: \(\left(\frac{1}{49}-\frac{1}{2^2}\right)\times\left(\frac{1}{49}-\frac{1}{3^2}\right)\times...\times\left(\frac{1}{49}-\frac{1}{40^2}\right)\)