thực hiện phép tính rồi rút gọn

A=\(\left(\frac{4}{9}+\frac{5}{6}\right):\left(\frac{7}{8}-\frac{7}{12}\right)\)

B=\(\frac{3}{4}.\frac{8}{9}.\frac{15}{16}...\frac{9999}{10000}\)

C=\(\left[3-\frac{1}{5}+\frac{3}{10}\right]:\left(2+\frac{1}{4}-\frac{3}{5}\right)\)

Rút gọn các biểu thức sau :

a) \(A=\)\(\frac{4^5.9^4-2.6^9}{2^{10}.3^8+6^8.20}\)

b) \(B=\)\(\frac{\left(\frac{2}{3}\right)^3.\left(\frac{-3}{4}\right)^2.\left(-1\right)^5}{\left(\frac{2}{5}\right)^2.\left(\frac{-5}{12}\right)^3}\)

rút gọn rồi quy đồng các phân số sau đây:

a)  \(\frac{7.12^3+2.12^3}{4^6.3^{11}};\frac{-17.10+17.6}{18.11+18.6};\frac{6.7.8.10}{9.12.14.15}\)

b)  \(\frac{4.3^9+8.\left(-3\right)^7}{\left(-3\right)^{10}+20.\left(-3\right)^7};\frac{5^6.8-5^7}{5^8-7.5^6};\frac{-1997.1996+1}{-1995.\left(-1997\right)+1996}\)

Rút gọn:

a,\(A=\frac{5\cdot4^{15}\cdot9^9-4\cdot3^{20}\cdot8^9}{5\cdot2^9\cdot6^{19}-7\cdot2^{29}\cdot27^6}\)

b,\(B=\left(1+\frac{1}{1\cdot3}\right)\left(1+\frac{1}{2\cdot4}\right)\left(1+\frac{1}{3\cdot5}\right)...\left(1+\frac{1}{2014\cdot2016}\right)\)

thực hiện các phép tính sau:

\(a,\left(4\frac{5}{37}-3\frac{4}{5}+8\frac{15}{29}\right)-\left(3\frac{5}{37}-6\frac{14}{29}\right)\)

\(b,\left(2\frac{5}{6}+1\frac{4}{9}\right):\left(10\frac{1}{12}-9\frac{1}{2}\right)\)

\(c,-\frac{2}{3}\left(8\frac{1}{2}-7.75\right):\frac{1}{3}+0.125:2\frac{2}{3}\)

1 tính 

a \(\left(\frac{9}{14}-\frac{9}{21}\right):\left(\frac{4}{5}+\frac{5}{6}\right)\)

b \(\frac{7}{10}-\frac{-3}{4}+\frac{-5}{6}-\frac{1}{5}+\frac{-2}{3}\)

c \(\left(-2\right)^2.\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)

d \(-\frac{1}{7}.\left(9\frac{1}{2}-0,75\right):\frac{2}{7}+0,625:1\frac{2}{3}\)

\(^{\left(8-\frac{9}{4}+\frac{2}{7}\right)-\left(-6-\frac{3}{7}+\frac{5}{4}\right)-\left(3+\frac{2}{4}-\frac{9}{7}\right)}\)