Question

1/(1×2) + 1/ ( 2×3) +1/ (3×4) +................+1/(999×1000) +1

Answer 1

La 1,999 nha!

Answer 2

Là 1,999 mình học rồi

Answer 3

\(\frac{1999}{1000}\)

ủng hộ mk

Answer 4

$\frac{1}{1\cdot 2}+\frac{1}{2\cdot 3}+\frac{1}{3\cdot 4}+...+\frac{1}{999\cdot 1000}+1$

= $\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{999}-\frac{1}{1000}+1$

= $\frac{1}{1}-\frac{1}{1000}+1$ 

=$\frac{999}{1000}+1$

=$\frac{999}{1000}+\frac{1000}{1000}$

=$\frac{1999}{1000}$