A=1+1/2=1/2^2+1/2^3+………….+1/2^2021

A=1+1/2=1/2^2+1/2^3+………….+1/2^2021

0 bình luận về “A=1+1/2=1/2^2+1/2^3+………….+1/2^2021”

  1. `A= 1 + 1/2 + 1/2^2 + 1/2^3 +…+1/2^2021`

    `1/2A= 1/2(1+1/2 + 1/2^2 + 1/2^3+…+1/2^2021)`

    `1/2 A= 1/2 + 1/2^2 + 1/2^3 +…+1/2^2022`

    `A- 1/2A= 1+ 1/2 + 1/2^2 + 1/2^3+…+1/2^2021 – 1/2 – 1/2^2 – 1/2^3 -…-1/2^2022`

    `1/2A= 1 – 1/2^2022`

    `A= (1-1/2^2022) : 1/2`

    `A= (1- 1/2^2022). 2`

    `A= 2- 1/2^2021`

    Vậy `A= 2-1/2^2021`

     

    Bình luận

Viết một bình luận