Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 6: A=1+11+11 mũ 2 +…+ 11 mũ 2020 +11 mũ 2021

Toán Lớp 6: A=1+11+11 mũ 2 +…+ 11 mũ 2020 +11 mũ 2021

Comments ( 2 )

  1. A=1+11+$11^{2}$ +$11^{3}$+…+$11^{2020}$ +$11^{2021}$ 
    11A=$11^{1}$+ $11^{2}$ +…+$11^{2021}$ +$11^{2022}$ 
    11A-A=$11^{2022}$-1
    A=$\dfrac{11^{2022} -1}{11}$
     Hội developer muôn năm ????

  2. A = 1 + 11 + 11^2 +…+ 11^2020 + 11^2021
    11A = 11(1 + 11 + 11^2 +…+ 11^2021)
    11A = 11 + 11^2 + 11^3 +…+ 11^2022
    11A – A = (11 + 11^2 + 11^3 +…+ 11^2022) – (1 + 11 + 11^2 +…+ 11^2021)
    10A = 11 + 11^2 + 11^3 +…+ 11^2022 – 1 – 11 – 11^2 -…- 11^2021
    10A = (11 – 11) + (11^2 – 11^2) +…+ (11^2021 – 11^2021) + 11^2022 – 1
    10A = 11^2022 – 1
    A = (11^2022 – 1)/10
     

Leave a reply

222-9+11+12:2*14+14 = ? ( )

About Kim Xuân