Tính `A=` `1/[1.3] +1/[2.4]+1/[3.5]+1/[4.6]`

1 bình luận về “Tính `A=` `1/[1.3] +1/[2.4]+1/[3.5]+1/[4.6]`”

1. A = 1/1.3 + 1/2.4 + 1/3.5 + 1/4.6

   = 1/1.3 + 1/3.5 + 1/2.4 + 1/4.6

   = 1/2(1 – 1/3 + 1/3 – 1/5 + 1/2 – 1/4 + 1/4 – 1/6)

   = 1/2(1 – 1/5 + 1/2 – 1/6)

   = 1/2(30/30 – 6/30 + 15/30 – 5/30)

   = 1/2. 17/15

   = 17/30

   Trả lời