Chứng minh rằng: 3/1^2×2^2+5/2^2×3^2+7/3^2×4^2+…+19/9^2×10^2<1 11/10/2021 Bởi Rose Chứng minh rằng: 3/1^2×2^2+5/2^2×3^2+7/3^2×4^2+…+19/9^2×10^2<1
3/1^2 . 2^2 + 5/2^2 . 3^2 + ... + 19/9^2 . 10^2 < 1 =1/1^2−1/2^2 + 1/2^2−1/3^2 +... + 1/9^10−1/10^2 =1−1/10^2 < 1 Bình luận
3/1^2 . 2^2 + 5/2^2 . 3^2 + ... + 19/9^2 . 10^2 < 1
=1/1^2−1/2^2 + 1/2^2−1/3^2 +... + 1/9^10−1/10^2
=1−1/10^2 < 1