Question

A=\(\frac{1}{1.3}\)+\(\frac{1}{3.5}\)+\(\frac{1}{5.7}\)+\(\frac{1}{7.9}\)+\(\frac{1}{9.11}\)+\(\frac{1}{11.13}\)+ .........+\(\frac{1}{101.103}\)

Rút gọn phân số  A

Answer 1

a = 1

+ các phân số lại sẽ có 1 

tk cho mk , mk tk  lại

Answer 2

A=1/3 - 1/103=(103-3)/3.103=100/309

Answer 3

\(A=\frac{1}{3.5}+\frac{1}{7.9}+\frac{1}{11.13}+..+\frac{1}{101.103}\)

\(A=\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+..+\frac{1}{101}-\frac{1}{103}\right).2\)

\(A=\left(1-\frac{1}{103}\right).2\)

\(A=\frac{102}{103}.2\)

\(A=\frac{204}{103}\)