Question

Ghi rõ cách làm cho mình nhé:

1/1 x 2+ 1/2 x 3+ 1/3 x 4+...+1/99 x100

Answer 1

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

1!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1

Answer 2

1/1 x 2 + 1/2x 3 + 1/3 x 4 + ... + 1/99 x 100 

= 1 - 1/2 + 1/2 - 1/3 + 1/3 - 1/4 + ...+ 1/99 - 1/100

= 1 - 1/100

= 100/100 - 1/100

=  99/100 

Chúc học giỏi !!! TK mình nha !! 

Answer 3

1/2346

Answer 4

\(\frac{1}{1x2}+\frac{1}{2x3}+\frac{1}{3x4}+.....+\frac{1}{99x100}\)

\(=\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{99}-\frac{1}{100}\)

\(=1-\frac{1}{100}\)

\(=\frac{100}{100}-\frac{1}{100}\)

\(=\frac{99}{100}\)

Tk mk nha!!

~ Hk tot~~

Answer 5

\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{99.100}\)

=1-\(\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{99}-\frac{1}{100}\)

=1-\(\frac{1}{100}\)

=\(\frac{99}{100}\)

Theo mình là như vậy có chỗ nào sai sót thì mình xin lỗi

Answer 6

cam on nhe