H9gh

=155 nha

99+56=155nha bn

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

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

\(=1-\frac{1}{100}=\frac{99}{100}\)

A B C 5cm 8cm

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

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

\(=1-\frac{1}{100}=\frac{99}{100}\)(Nhớ k cho mình với nhá!)

99/100

\(\frac{1}{1\times2}+\frac{1}{2\times3}+...+\frac{1}{99\times100}\)

A B C 5cm 8cm

J v bn ???

lấy hết mấy tờ đó cho khỏi đau đầu

\(A=\frac{1}{1x2}+\frac{1}{2x3}+...+\frac{1}{99.100}\)

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

\(A=\frac{1}{1}-\frac{1}{100}=\frac{99}{100}\)

\(A=\frac{1}{1\times2}+\frac{1}{2\times3}+...+\frac{1}{99\times100}\)

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

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

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

TL : 

Cạnh AC dài là : 102 + 12 + 25 = 139 ( cm )

~HT~

\(A=\frac{1}{1x2}+\frac{1}{2x3}+...+\frac{1}{99x100}\)

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

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

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

1/1×2 + 1/2×3 + ... + 1/99×100

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

= 1 - 1/100

= 99/100

Ủng hộ mk nha ♡_♡

1/1 NHÂN 2+1/1 NHÂN 3 + ... + 1/99 NHÂN 100

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

=1 - 1/100

=99/100

NHỚ K MK NHA CÁC BN CŨNG ỦNG HỘ NHÉ