\(=\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{4}+...+\dfrac{1}{99}-\dfrac{1}{100}\)
\(=\dfrac{1}{2}-\dfrac{1}{100}=\dfrac{49}{100}\)
tính:A=1/1x2+1/2x3+1/3x4+1/4x5+...+1/99x100
Tính tổng
1/2x3+1/3x4+1/4x5+.....+1/99x100
1/2x3+1/3x4+1/4x5+1/5x6=.......1/99x100
tính nhanh
\(\frac{1}{1x2}+\frac{1}{2x3}+\frac{1}{3x4}+\frac{1}{4x5}+....+\frac{1}{99x100}\)
1x2 + 2x3 + 3x4 + 4x5 + .... +99x100
A=1x2+2x3+3x4+4x5+...+99x100
Tính nhanh:. A = 1x2 + 2x3 + 3x4 + 4x5 + ... + 99x100.
Tính nhanh:.
A = 1x2 + 2x3 + 3x4 + 4x5 + ... + 99x100.
S= 1x2+2x3+3x4+4x5+...+98x99+99x100
