Tính:A= 8/1.5+8/5.9+8/9.13+……+8/101.105 A=4.2/1.5+4.2/5.9+4.2/9.13+….+4.2/101.105 Mng lm tiếp hộ e với ạ

0 bình luận về “Tính:A= 8/1.5+8/5.9+8/9.13+……+8/101.105 A=4.2/1.5+4.2/5.9+4.2/9.13+….+4.2/101.105 Mng lm tiếp hộ e với ạ”

1. `A = 8/1.5 + 8/5.9 + 8/9.13 + …. + 8/101.105`

   `A = ( 4/1.5 + 4/5.9 + 4/9.13 + … + 4/101.105 ) . 2`

   `A = ( 1/1 – 1/5 + 1/5 – 1/9 + … + 1/101 – 1/105 ) . 2`

   `A = ( 1/1 – 1/105 ) . 2`

   `A = 104/105 . 2`

   `A = 208/105`

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   `A = 4.2/1.5 + 4.2/5.9 + 4.2/9.13 + …. + 4.2/101 . 105`

   `A = ( 4/1.5 + 4/5.9 + 4/9.13 + ….. + 4/101.105 ) . 2`

   `A = ( 1/1 – 1/5 + 1/5 – 1/9 + 1/9 – 1/13 + … + 1/101 – 1/105 ) .2`

   `A = ( 1/1 – 1/105 ) . 2`

   `A = 104/105 . 2`

   `A = 208/105`

    

   Trả lời

2. Đáp án:

   `A=(4.2)/(1.5)+(4.2)/(5.9)+(4.2)/(9.13)+….+(4.2)/(101.105)`

   `A=2.(4/(1.5)+4/(5.9)+……………+4/(101.105))`

   `A=2.(1-1/5+1/5-1/9+………….+1/101-1/105)`

   `A=2.(1-1/105)`

   `A=2.(104/105)`

   `A=208/105`

   XIN HAY NHẤT NHA

    

   Trả lời