Question

[Aikatsu Starts Hime]

\(\frac{1}{1\times2}+\frac{1}{2\times3}+.....+\frac{1}{99\times100}\)

kb với mk nha

ai nhanh mk k ^_^

Answer 1

[Mạnh Lê]

Đặt \(A=\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{99.100}\)

\(A=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{99}-\frac{1}{100}\)

\(A=1-\frac{1}{100}\)

\(A=\frac{99}{100}\)

Answer 2

[Aikatsu Starts Hime]

cảm ơn bn nhìu ^_^