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 7: CMR 1/1.2+1/3.4+1/5.6+-…+1/49.50=1/26+1/27+1/28+-.+1/49+1/50 (CẤM LÀM TẮT) LÀM TẮT SẼ BỊ BÁO CÁO

Toán Lớp 7: CMR
1/1.2+1/3.4+1/5.6+…….+1/49.50=1/26+1/27+1/28+…..+1/49+1/50 (CẤM LÀM TẮT) LÀM TẮT SẼ BỊ BÁO CÁO

Comments ( 2 )

  1. Giải đáp:
     
    Lời giải và giải thích chi tiết:
    1/1.2 + 1/3.4 + 1/5.6 +………+ 1/49.50
    =1 – 1/2 + 1/3 – 1/4 + 1/5 – 1/6 +………+ 1/49 – 1/50
    =(1+1/3+1/5+………+1/49)-(1/2+1/4+1/6+……..+1/50)
    =(1+1/2+1/3+1/4+1/5+……..+1/49+1/50) – 2.(1/2+1/4+1/6+……..+1/50)
    =(1+1/2+1/3+1/4+1/5+……..+1/49+1/50) – (1+1/2+1/3+………+1/25)
    =1/26+1/27+1/28+………+1/49+1/50=1/26+1/27+1/28+………+1/49+1/50 ( ĐPCM )
    #Dung09

  2. Giải đáp+Lời giải và giải thích chi tiết:
    1/1.2+1/3.4+1/5.6+…+1/49.50=1/26+1/27+1/28+…+1/49+1/50
    = 1/1-1/2+1/3-1/4+…+1/49-1/50
    = (1/1+1/3+….+1/49)-(1/2+1/4+….+1/50)
    = (1/1+1/2+1/3+….+1/50)-2.(1/2+1/4+….+1/50)
    = 1/1+1/2+1/3+…..+1/50-1-1/2-1/3-…..-1/25
    = 1/26+1/27+1/28+…..+1/49+1/50 (đpcm)

Leave a reply

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

About Nhi