\(\left(\frac{2012}{2015}+\frac{2011}{2016}+\frac{2010}{2017}+\frac{2009}{2018}\right)\cdot\left(\frac{1}{6}+\frac{1}{3}+\frac{1}{2}\right)\)
giúp mình giải bài này với !!!!!!
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+...+\frac{2}{x\left(x-1\right)}=\frac{2007}{2009}\)
Tìm X : \(1+\frac{2}{6}+\frac{2}{12}+\frac{2}{20}+...+\frac{2}{x.\left(x+1\right)}=1\frac{2009}{2011}\)
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+...+\frac{2}{x\left(x-1\right)}=\frac{2007}{2009}\)
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+.....+\frac{2}{x\left(x-1\right)}=\frac{2007}{2009}\)
Tìm x, biết:
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{2}{x.\left(x+1\right)}=\frac{2011}{2013}\)
tìm x
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+.....+\frac{2}{x\cdot\left(x+1\right)}=\frac{2011}{2013}\)
Tìm \(x\):
\(\left(\frac{1}{1\times2}+\frac{1}{2\times3}+\frac{1}{3\times4}+.....\frac{1}{2009\times2010}\right)\times x=2009\)
Tính giá trị biểu thức:
\(A=\frac{\frac{16}{10}:\left(1\frac{3}{5}\times \frac{5}{4}\right)}{\frac{64}{100}-\frac{1}{25}}+\frac{\left(\frac{108}{100}-\frac{2}{25}\right):\frac{4}{7}}{\left(5\frac{5}{9}-2\frac{1}{4}\right)\times 2\frac{2}{17}}+\frac{3}{5}\times \frac{1}{2}:\frac{2}{5}\)