Tính tổng;
\(\frac{1}{1.2.3}+\frac{1}{2.3.4}+\frac{1}{3.4.5}+...+\frac{1}{37.38.39}\)
Tính tổng: \(\frac{1}{1.2.3}+\frac{1}{2.3.4}+\frac{1}{3.4.5}+...+\frac{1}{37.38.39}\)
Tính:
a) \(S=\frac{1}{1.2.3}+\frac{1}{2.3.4}+\frac{1}{3.4.5}+...+\frac{1}{37.38.39}\)
(3 like ko thiếu cái nào
Tìm x, biết
a) C=\(\frac{2}{1.2.3}+\frac{2}{2.3.4}+...+\frac{2}{37.38.39}\)
Tính tổng
\(\frac{1}{1.2.3}+\frac{1}{2.3.4}+\frac{1}{3.4.5}+...+\frac{1}{2006.2007.2008}\)
\(\frac{\left(1.2+2.3+3.4+.....+98.99\right)y}{1}=184800\) tim y
2\ \(\left(\frac{1}{1.2.3}+\frac{1}{2.3.4}+\frac{1}{3.4.5}+.....\frac{1}{37.38.39}\right).1428+185,8\) tinh gia tri cua bieu thuc tren
Tính tổng \(\frac{1}{1.2.3}+\frac{1}{2.3.4}+...+\frac{1}{a\left(a+1\right)\left(a+2\right)}\)
Tính \(A=\frac{1}{1.2.3}+\frac{1}{2.3.4}+\frac{1}{3.4.5}+.....+\frac{1}{99.100.101}\)
Tính
A = \(\frac{1}{1.2.3}-\frac{1}{2.3.4}-.......-\frac{1}{99.100.101}\)
