S=1+1/2.5+1/5.8+1/8.11+1/11.14+…+1/24×27+1/27.30

0 bình luận về “S=1+1/2.5+1/5.8+1/8.11+1/11.14+…+1/24×27+1/27.30”

1. `#DyHungg`

   `S=1+1/(2.5)+1/(5.8)+1/(8.11)+…+1/(24/27)+1/(27.30)`

   `3S=3+(3/2-3/5+3/5-3/8+3/8-3/11+…+3/24-3/27)`

   `3S=3+(1/2-1/30)`

   `3S=3+7/15`

   `3S=52/15`

   `S=52/15:3=52/45`

   Trả lời

2. `S= 1 + 1/2.5 + 1/5.8+ 1/8.11 +…+ 1/27.30`

   `3S= 3 + 3/2.5 + 3/5.8 + 3/8.11 +…+ 3/27.30`

   `3S= 3 + 1/2 – 1/5 + 1/5 – 1/8 +…+ 1/27- 1/30`

   `3S= 3+ 1/2 – 1/30`

   `3S= 7/2 – 1/30`

   `3S= 52/15`

   `S= 52/15 : 3`

   `S= 52/15 . 1/3`

   `S=52/45`

   Vậy `S= 52/45`

    

   Trả lời