`Q = -5/{99 . 97} - 5/{97 . 95} - 5/{95 . 93} - ... - 5/{7 . 5} - 5/{5 . 3} - 5/{3 . 1}`

`Q = - ( 5/{1.3} + 5/{3.5} + 5/{5.7} + ... + 5/{93.95} + 5/{95.97} + 5/{97.99})`

`Q = {-5}/2 . ( 2/{1.3} + 2/{3.5} + 2/{5.7} + ... + 2/{93.95} + 2/{95.97} + { 2/{97.99})`

`Q = {-5}/2 . ( 1- 1/99 )`

`Q = {-5}/2 . 98/99`

`Q = {-245}/99`

Vậy `Q = {-245}/99`

`color{blue}{Zata5tich}`