\(\left(\frac{5}{12}+\frac{1}{2}.\frac{1}{3}\right):\left(2.\frac{1}{3}-1.\frac{5}{12}\right)\)

\(=\left(\frac{5}{12}+\frac{1}{6}\right):\left(\frac{2}{3}-\frac{5}{12}\right)\)

\(=\frac{7}{12}:\frac{1}{4}\)

\(=\frac{7}{3}\)

_Chúc bạn học tốt_

sửa đề nhé:

\(\frac{5}{1\times3}+\frac{5}{3\times5}+...+\frac{5}{99\times101}\)

\(5\times\frac{1}{2}\times\left(\frac{2}{1\times3}+\frac{2}{3\times5}+...+\frac{2}{99\times101}\right)\)

\(=\frac{5}{2}\times\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+...+\frac{1}{99}-\frac{1}{101}\right)\)

\(=\frac{5}{2}\times\left(1-\frac{1}{101}\right)\)

\(=\frac{5}{2}\times\frac{100}{101}\)

\(=\frac{250}{101}\)

mong cac ban giup

1.5+1.5

=5+5

=10

=10

các bạn cho mình vài li-ke cho tròn 545 với 

1.5+1.5

=5+5

=10

cao phan tuấn anh : ko làm mà mơ đc tick

                     Ta có :

                     \(A=\frac{4}{1.5}+\frac{5}{5.10}+\frac{6}{10.16}+\frac{7}{16.23}+\frac{8}{23.31}+\frac{9}{31.40}\)

                    \(A=1-\frac{1}{5}+\frac{1}{5}-\frac{1}{10}+\frac{1}{10}-\frac{1}{16}+\frac{1}{16}-\frac{1}{23}+\frac{1}{23}-\frac{1}{31}+\frac{1}{31}-\frac{1}{40}\)

                   \(A=1-\frac{1}{40}=\frac{39}{40}\)

                   Ủng hộ mk nha !!! ^_^

\(\left(2007-2005\right)+\left(2003-2001\right)+...+\left(7-5\right)+\left(3-1\right)\)

\(=2+2+...+2\)

\(=2.1004=2008\)

\(\dfrac{1}{1.5};\dfrac{1}{5.9};\dfrac{1}{9.13};\dfrac{1}{13.17}\)