Các câu hỏi tương tự
CT: 1/1x2+ 1/1x2x3+ 1/1x2x3x4+ ..................+ 1/1x2x3x4x5.........100
Tìm số tự nhiên n để số A= 1+1x2+1x2x3+...+1x2x3x...xn là số chính phương (n thuộc N*)
1x2+1x2x3+1x2x3x4+1x2x3x4x5+....+1x2x3...99x100
Tìm số tự nhiên n để số A =1+1x2+1x2x3+....+1x2x3x...xn (n thuộc N*) là số chính phương
Làm chi tiết giúp mk nha
C1x2+2x3+3x4+........+99x100D1x2x3+2x3x4+3x4x5+.......+98x99x100E12+22+52+.......+992F1/1x2+1/2x3+..........+1/99x100G1/1x2x3+1/2x3x4+........+1/99x98x100H 1/1x2x3x4+1/3x4x5x6+............+1/97x98x99x100K 1+1/2(1+2)+1/3(1+2+3)+........+1/30(1+2+30)L1/21+1/22+1/23+1/24+..............+1/210M2015/2015x2017-20162frac{ }{ }
Đọc tiếp
C=1x2+2x3+3x4+........+99x100
D=1x2x3+2x3x4+3x4x5+.......+98x99x100
E=12+22+52+.......+992
F=1/1x2+1/2x3+..........+1/99x100
G=1/1x2x3+1/2x3x4+........+1/99x98x100
H= 1/1x2x3x4+1/3x4x5x6+............+1/97x98x99x100
K= 1+1/2(1+2)+1/3(1+2+3)+........+1/30(1+2+30)
L=1/21+1/22+1/23+1/24+..............+1/210
M=2015/2015x2017-20162
\(\frac{ }{ }\)
3x - (1/1x2+1/2x3+.....+1/99x100)=1/1x2x3+1/2x3x4+......+1/18x19x20
a. 1/1x2 + 1/2x3 +...+ 1/2006x2007b. 2006/1x2 + 2006/2x3 +...+ 2006/2006x2007c. 1/1x2x3 + 1/2x3x4 +...+ 1/2004x2005x2006
Xem chi tiết
(1/1x2+1/2x3+1/3x4.....1/7x8+1/8x9)x100-[5/2-(x+206/100)]:1/2=89
Tính :
a) 1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+.....+1
b)1/1x2x3+1/2x3x4+1/3x4x5+.....+1/98x99x100