chứng minh rằng : a)1/1.2+1/2.3+1/3.4+…+1/40.50 <1 b)1/3^2+1/4^2+1/5^2 +1/6^1+...+1/100^2 <1/2 19/09/2021 Bởi Emery chứng minh rằng : a)1/1.2+1/2.3+1/3.4+…+1/40.50 <1 b)1/3^2+1/4^2+1/5^2 +1/6^1+...+1/100^2 <1/2
a) 1/1.2+1/2.3+1/3.4+…+1/40.50<1 ta có : 1-1/2+1/2-1/3+1/3-1/4+…+1/40-1/50 =1-1/50 =49/50<1 =>1/1.2+1/2.3+1/3.4+…+1/40.50<1 mk chỉ bk làm câu a thôi nha bạn Bình luận
a) 1/1.2+1/2.3+1/3.4+…+1/40.50<1
ta có : 1-1/2+1/2-1/3+1/3-1/4+…+1/40-1/50
=1-1/50
=49/50<1
=>1/1.2+1/2.3+1/3.4+…+1/40.50<1
mk chỉ bk làm câu a thôi nha bạn