Các câu hỏi tương tự
P = 1/1.2.3 + 1/2.3.4 + 1/3.4.5 +...+ 1/n(n+1)(n+2)
S = 1/1.2.3 + 1/2.3.4 + 1/3.4.5 +...+ 1/48.49.50 .
P=1/1.2.3+1/2.3.4+1/3.4.5+...+1/10.11.12
1/1.2.3+1/2.3.4+1/3.4.5+...+1/37.38.39
1/1.2.3 + 1/2.3.4 + 1/3.4.5+...+1/98.99.100 = ?
1/1.2.3 + 1/2.3.4 + 1/3.4.5 + ...+1/98.99.100 =?
1/1.2.3+1/2.3.4+1/3.4.5+....+1/37.38.39 = ?
1/1.2.3+1/2.3.4+1/3.4.5+...+1/37.38.39
1/1.2.3+1/2.3.4+1/3.4.5+...+1/37.38.39
Tính : a, 1.2.3 + 2.3.4 + 3.4.5 + ... + (n - 1).n.(n+1)
b, 1.2.3 + 3.4.5 + 5.6.7 + 98.99.100