Question

[Cure Dream]

\(\frac{1}{1X2}\)+ \(\frac{1}{2X3}\)+ \(\frac{1}{3X4}\)+ ... + \(\frac{1}{999X1000}\)+ 1

Giúp mk bài náy vs nhé mk tk cho

Answer 1

[Nam Đinh Hoàng]

1+1/1 - 1/1000 = tự tính nhé

Answer 2

[NGUYỄN THẾ HIỆP]

\(\frac{1}{1x2}+\frac{1}{2x3}+...+\frac{1}{999x1000}+1\)

\(=\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{999}-\frac{1}{1000}+1\)

\(=2-\frac{1}{1000}=\frac{1999}{1000}\)