\(\frac{3}{1^2\cdot2^2}+\frac{5}{2^2\cdot3^2}+...+\frac{19}{9^2\cdot10^2}\)\(=\frac{1}{1^2}-\frac{1}{2^2}+\frac{1}{2^2}-\frac{1}{3^2}+...+\frac{1}{9^2}-\frac{1}{10^2}=1-\frac{1}{10^2}=\frac{99}{100}\)<1
Bài 1: CMR 3/1^2*2^2 + 5/2^2*3^2 + 7/3^2*4^2 + ....... + 19/9^2*10^2 bé hơn 1
Bài 2: CMR 1/3 + 2/3^2 Bài 1: CMR 3/1^2*2^2 + 5/2^2*3^2 + 7/3^2*4^2 + ....... + 19/9^2*10^2 bé hơn 3/4
Bài 3: Cho A= 1/1*2 + 1/3*4 + 1/5*6 + .... + 1/99*100. CMR 7/12 < A < 5/6
cmr : 3/1^2 . 2^2 + 5/2^2 . 3^2 + 7/3^2 . 4^2 + ....+ 19/9^2 . 10^2 < 1
cmr: 3/1^2 x 2^2 + 5/2^2 x 3^2 + ... = 19/9^2 x 10^2
CMR A=3/1^2+2^2+5/2^2+3^2+7/3^2+4^2+....19/9^2+10^2 <1
trả lời được thì mình kết bạn nha
CMR : \(\frac{3}{1^2.2^2}+\frac{5}{2^2.3^2}+\frac{7}{3^2.4^2}+...+\frac{19}{9^2+10^2}\)< 1
CMR : 3/1^2.2^2 + 5/2^2.3^2 + 7/3^2.4^2 + ... + 19/9^2.10^2 < 1
Chứng minh rằng \(\dfrac{3}{1^2+2^2}+\dfrac{5}{2^2+3^2}+...+\dfrac{19}{9^2+10^2}\) < 1.
CMR: \(\frac{3}{1^2.2^2}+\frac{5}{2^2.3^2}+\frac{7}{3^2.4^2}+...+\frac{19}{9^2.10^2}< 1\)
