3^4+8^9+15/16+...+1599/1600 lớn hơn 38
Chứng mih rằng : 3/4 +8/9 +15/16+...+ 1599/1600>38
A= 1/2 . 3/4 . 5/6 ... 1599/1600
cmr A <2/3. 4/5 . 6/7... 1600/1601
A= 1/2 . 3/4 . 5/6 ... 1599/1600
cmr A <2/3. 4/5 . 6/7... 1600/1601
A= 1/2 . 3/4 . 5/6 ... 1599/1600
cmr A <0,025
A= 1/2 . 3/4 . 5/6 ... 1599/1600
cmr A <0,025
Cho c=3/4+8/9+15/16+...+2499/2500
CMR C lớn hơn 48 biết C có 49 số hạng
CMR 3/4+8/9+15/16+...+1499/2500>48
Cmr 3/4 + 8/9 + 15/16 + ... + 2499/2500 > 48