tính giá trị biểu thức: 1/1.2.3.4 + 1/2.3.4.5 + 1/3.4.5.6 +...+1/27.28.29.30
tính
a) 2/3.5+2/5.7+2/7.9+2/9.11+2/11.13
b) 1/1.2.3.4+1/2.3.4.5+1/3.4.5.6+1/27.28.29.30
1/1.2.3.4+1/2.3.4.5+......+1/27.28.29.30
mn giải giúp mik nhé mik tik cho
\(y=\frac{1}{1.2.3.4}+\frac{1}{2.3.4.5}+...+\frac{1}{27.28.29.30}\)
Tính giá trị biểu thức :
a) 1/1.2.3 + 1/2.3.4 + 1/3.4.5 + ...... + 1/27.28.29
b) 1/1.2.3.4 + 1/2.3.4.5 + 1/3.4.5.6 + ..... + 1/27.28.29.30
Khẩn cấp nhé
Tính: a) B= 36/1.3.5 + 36/3.5.7 + ... + 36/ 25.27.29
b) M= 1/1.2.3.4 + 1/2.3.4.5 + ... + 1/27.28.29.30
bài1Tính a,B=1/1.2.3.4+1/2.3.4.5+1/3.4.5.6+...+1/27.28.29.30
b,1.2.3+2.3.4+3.4.5+...+48.49.50
1 tinh
a/ 1/1.2.3+1/2.3.4+1/3.4.5+...+1/98.99.100
b/ 1/1.2.3.4+1/2.3.4.5+1/3.4.5.6+...+1/27.28.29.30
tính nhanh
A= \(\frac{1}{1.2.3.4}\)+\(\frac{1}{2.3.4.5}\)+\(\frac{1}{3.4.5.6}\)+.........+\(\frac{1}{27.28.29.30}\)