1/2x3 +1/3x4 +..........+ 1/ax(a+1)=299/600
=>1/2-1/3+1/3-1/4+.........+ 1/a -1/a+1=299/600
=>1/2-1/a+1=299/600
=>a-1/2a=299/600
=>a=300
tìm a biết 1/2x3+ 1/3x4+1/4x5 +...+1/ax(ax1)=49/100
Tìm số tự nhiên A biết : 1/2X3+ 1/3X4+1/4X5+...+1/Ax(a+1)=49/100
Tìm x biết 1/2x3+1/3x4+.......+1/xx(x+1) =299/600
Calculate: 1/2x3+1/3x4 + 1/4x5+...+1/98 x 99 = A /198 Answer: A =
Tìm số tự nhiên a biết 1/2x3+1/3x4+1/4x5+......+1/a x(a+1)=49/100
1/2x3+1/3x4+1/4x5+....+1/99x100=?
1/2x3 + 1/3x4 + 1/4x5 + ... + 1/9x10 = ?
1/2x3+1/3x4+1/4x5+,.......+1/29x30
tính:A=1/1x2+1/2x3+1/3x4+1/4x5+...+1/99x100
