\(\frac{4}{1.5}+\frac{4}{5.9}+\frac{4}{9.13}+...+\frac{4}{177.181}+\frac{4}{181.185}\)
\(=\left(\frac{1}{1}-\frac{1}{5}\right)+\left(\frac{1}{5}-\frac{1}{9}\right)+\left(\frac{1}{9}-\frac{1}{13}\right)+...+\left(\frac{1}{177}-\frac{1}{181}\right)+\left(\frac{1}{181}-\frac{1}{185}\right)\)
\(=\frac{1}{1}-\frac{1}{185}\)
\(=\frac{184}{185}\)
Tính tổng M=-4/1.5-4/5.9-4/9.13-…-4/(n+4.)n
Tính tổng M=-4/1.5-4/5.9-4/9.13-…-4/(n+4.)n
a) 1/2.4 + 1/4.6 + 1/6.8 + 1/8.10
b) 4/1.5 + 4/5.9 + 4/ 9.13 + 4/ 13.17
Tính M=\(-\frac{4}{1.5}-\frac{4}{5.9}-\frac{4}{9.13}-...-\frac{4}{\left(n-4\right).n}\)
Tính tổng:\(M:-\frac{4}{1.5}-\frac{4}{5.9}-\frac{4}{9.13}-...-\frac{4}{\left(n+4\right)n}.\)
\(A=\frac{4}{1.5}+\frac{4}{5.9}+\frac{4}{9.13}+.....+\frac{4}{29.33}\)=?
Tính :
A, 4/1.5 + 4/ 5.9 + 4/ 9.13 + .... + 4/ (n-4).n ( n khác 4 , n khác 0 )
Mk sẽ tick nha
tính :S=\(\frac{-4}{1.5}-\frac{4}{5.9}-\frac{4}{9.13}......-\frac{4}{\left(n-4\right)n}\left(n\in N\right)\)