Biết \(\frac{1}{40}+\frac{1}{88}+\frac{1}{154}+...+\frac{1}{x\times\left(x+3\right)}=\frac{101}{1540}\) .Khi đó x=.............
Tìm x biết \(\frac{2}{40}+\frac{2}{88}+\frac{2}{154}+....+\frac{2}{x\left(x+3\right)}=\frac{202}{1540}\)
x.\(\frac{1}{10}\)+\(\frac{1}{88}\)+\(\frac{1}{154}\)+...+\(\frac{1}{x.\left(x+3\right)}\)=\(\frac{101}{1540}\)
Tìm x biết:
\(\frac{2}{40}+\frac{2}{88}+\frac{2}{154}+...+\frac{2}{x\left(x+3\right)}=\frac{202}{1540}\)
tìm x biết :
\(\frac{2}{40}+\frac{2}{88}+\frac{2}{154}+.....+\frac{2}{x\left(x+3\right)}=\frac{202}{1540}\)
Tìm x biết: \(\frac{1}{5\times8}+\frac{1}{8\times11}+\frac{1}{11\times14}+...+\frac{1}{x\left(x+3\right)}=\frac{101}{1540}\)
tìm x biết
\(\frac{1}{3.5}+\frac{1}{5.7}+.....+\frac{1}{x.\left(x-3\right)}=\frac{101}{1540}\)
Tìm x, biết:
\(\frac{1}{58}+\frac{1}{811}+\frac{1}{1114}+...+\frac{1}{x\left(x+3\right)}=\frac{101}{1540}\)
Tìm x, biết rằng:
a)\(\frac{1}{5.8}+\frac{1}{8.11}+\frac{1}{11.14}+...+\frac{1}{x\left(x+3\right)}=\frac{101}{1540}\)
b)\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)