tính nhanh:
\(\frac{5}{1.4}+\frac{5}{4.7}+\frac{5}{7.10}+.........+\frac{5}{100.103}\)
Bài 3 Tính giá trị biểu thức\(\left(1_{ },5\right).\frac{-2}{3}+\left(2,5-\frac{3}{4}\right):1\frac{3}{4}\)
B=\(\frac{1}{1.4}+\frac{1}{4.7}+\frac{1}{7.10}+...+\frac{1}{100.103}\)
tính tổng
\(s=\frac{3}{1.4}+\frac{3}{4.7}+\frac{3}{7.10}+...+\frac{3}{100.103}+\frac{1}{103.104}+\frac{1}{104.105}+\frac{1}{105.106}+\frac{1}{106.107}\)
Viết dạng tổng quát bài sau:\(\frac{1}{1.4}\)+\(\frac{1}{4.7}\)+\(\frac{1}{7.10}\)+...+\(\frac{1}{100.103}\)
\(\frac{5}{1.4}+\frac{5}{4.7}+.....+\frac{5}{100.103}\)
\(S=\frac{5}{1.4}+\frac{5}{4.7}+...+\frac{5}{100.103}=?\)
Tính :
D= \(\frac{5}{1.4}\)+ \(\frac{5}{4.7}\)+ .....+\(\frac{5}{100.103}\)
Tính:
a) \(\frac{5}{1.4}+\frac{5}{4.7}+...+\frac{5}{100.103}\)
b) \(\frac{1}{15}+\frac{1}{35}+...+\frac{1}{2499}\)
Tính tổng:
B= \(\frac{5}{1.4}\)+ \(\frac{5}{4.7}\)+...+\(\frac{5}{100.103}\)