Giải thích các bước giải:
a) `M = ( 1 - 1/4 ) .( 1 - 1/9 ) . ( 1 - 1/16 ) . .... . ( 1 - 1/10000 ) `
`=>M= 3/4 . 8/9 . 15/16 ... 9999/10000`
`=>M = 1.3/2.2 . 2.4/3.3 . 3.5/4.4 ... 99.101/100.100`
`=>M=(1.2.3...99)/(2.3.4...100).(3.4.5...101)/(2.3.4...100)`
`=>M=1/100. 101/2`
`=>M=101/200`
b) `N = ( 1 - 2/6.7 ) . ( 1 - 2/7.8 ) . ( 1 - 2/8.9 ) . .... . ( 1 - 2/51.52 )` (câu này nó kiểu gì ấy bạn ạ)
c) `Q = ( 1 + 1/1.3 ) . ( 1 + 1/2.4 ) . ( 1 + 1/3.5 ) . .... . ( 1 + 1/99.101 )`
`=>Q= 4/3 . 9/8 . 16/15 ... 10000/9999`
`=>Q = 2.2/1.3 . 3.3/2.4 . 4.4/3.5 ... 100.100/99.101`
`=>Q=(2.3.4...100)/(1.2.3...99).(2.3.4...100)/(3.4.5...101)`
`=>Q=100/1. 2/101`
`=>Q=200/101`