Đáp án:
`R = (1 + 1/2) (1 + 1/3) (1 + 1/4) ... (1 + 1/2012)`
`-> R = 3/2 . 4/3 . 5/4 .. 2013/2012`
`-> R = 2013/2`
`text{Vậy R}` = 2013/22`
`Q = 1^2/(1 . 2) + 2^2/(2 . 3) + 3^2/(3 . 4) + ... + 99^2/(9 . 100)`
`-> Q = 1/2 . 2/3 . 3/4 ... 99/100`
`-> Q = (1 . 2 . 3 ... 99)/(2 . 3 . 4 ... 100)`
`-> Q = 1/100`
`text{Vậy Q}` ` = 1/100`
`G = 1 13/15 . (0,5)^2 . 3 + (8/15 - 1 19/60) : 1 23/24`
`-> G = 28/15 . 1/4 + (8/15 - 79/60) : 47/24`
`-> G = 7/15 + (-47)/60 : 47/24`
`-> G = 7/15 + (-2)/5`
`-> G = 1/15`
`text{Vậy G}` = `1/15`
`K = (5/22 + 3/13- 1/2)/(4/13 - 2/11 + 3/2)`
`-> K = (131/286 - 1/2)/(18/143 + 3/2)`
`-> K = (-6/143)/(456/286)`
`-> K = (-4)/155`
`text{Vậy K}` `= (-4)/155`