\(\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{\frac{2}{3}-\frac{2}{7}-\frac{2}{13}}\cdot\frac{\frac{3}{4}-\frac{3}{16}-\frac{3}{64}-\frac{3}{264}}{1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}}+\frac{5}{8}\)

\(=\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{2\left(\frac{1}{3}-\frac{1}{7}-\frac{1}{13}\right)}\cdot\frac{\frac{3}{4}\left(1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}\right)}{1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}}\)\(+\frac{5}{8}\)

\(\frac{1}{2}\cdot\frac{3}{4}+\frac{5}{8}=\frac{3}{8}+\frac{5}{8}=1\)

= \(\frac{6}{10}-\frac{12}{30}\)

= \(\frac{18}{30}-\frac{12}{30}\)

= \(\frac{6}{30}=\frac{1}{5}\)

\(\frac{3}{4}.\frac{2}{5}-\frac{3}{10}.\frac{4}{3}\)

\(=\frac{3.2}{4.5}-\frac{3.4}{10.3}\)

\(=\frac{3}{10}-\frac{4}{10}=\frac{-1}{10}\)

ha Le ha sai bét, zậy mà Tran Hoang Vy - cậu vẫn chọn đk àk, thử tính lại = mt cái koai, = -1/10 CHỨ KO PHẢI =   1/10

\(A=\frac{3}{1}+\frac{3}{\frac{\left(2+1\right).2}{2}}+\frac{3}{\frac{\left(3+1\right).3}{2}}+....+\frac{3}{\frac{\left(100+1\right).100}{2}}\)

\(\Rightarrow A=\frac{3}{1}+\frac{6}{2.3}+\frac{6}{3.4}+...+\frac{6}{100.101}\)

\(\Rightarrow A=\frac{3}{1}+6.\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-...-\frac{1}{101}\right)\)

\(\Rightarrow A=\frac{3}{1}+6.\left(\frac{1}{2}-\frac{1}{101}\right)\)

\(\Rightarrow A=\frac{3}{1}+\frac{6.99}{202}=\frac{297}{101}+\frac{3}{1}=\frac{600}{101}\)

kết quả k bik có sai k

\(\frac{x+5}{3}=\frac{5}{9}\)

=> ( x + 5 ) x 9 = 3 x 5

=> x + 5 = \(\frac{3\cdot5}{9}\)

=> x + 5 = \(\frac{5}{3}\)

=> x = \(\frac{-10}{3}\)

x+5/3=5/9   

(x+5)x3/9=5/9

(x+5)x3=5

x+5=5:3

x+5=5/3

x=5/3-5

x=-10/3

x+5/3=5/9

[x+5]x9=5x3

x+5=[5x3]/9

x+5=5/3

x=5/3-5=-10/3

x-2/27=3/x-2

[x-2]^2=27x3

[x-2]^2=9^2

=>x-2=9

x=9+2=11

\(P=\frac{\frac{3}{7}-\frac{3}{13}+\frac{3}{37}}{\frac{5}{7}-\frac{5}{17}+\frac{5}{37}}+\frac{\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}}{\frac{7}{5}-\frac{7}{4}+\frac{7}{3}-\frac{7}{2}}\)

\(=\frac{3\left(\frac{1}{7}-\frac{1}{13}+\frac{1}{37}\right)}{5\left(\frac{1}{7}-\frac{1}{17}+\frac{1}{37}\right)}+\frac{\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}}{-7\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}\right)}\)

\(=\frac{3}{5}+\frac{1}{-7}\)

\(=\frac{16}{35}\)