Các câu hỏi tương tự
\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+............+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
Tính tổng
\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
Tìm x, biết rằng:
\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
tìm x::
1+\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
tìm x:
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+....+\frac{1}{x.\left(x+1\right):2}=\frac{1991}{1993}\)
Tính tổng :
\(\left(1-\frac{1}{2^2}\right)+\left(1-\frac{1}{3^2}\right)+\left(1-\frac{1}{4^2}\right)+....+\left(1-\frac{1}{50^2}\right)\)
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)\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
Tìm x biết:
\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+3\right):2}=1\frac{1991}{1993}\)
tìm x biết
\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
Tìm x
(-x-4)4=256
\(1+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{1}{x\left(x+1\right):2}=1\frac{1991}{1993}\)
\(\frac{1}{3.5}+\frac{1}{5.7}+...+\frac{1}{\left(x+2\right)x}=\frac{103}{104}\)