Question

Bài 1: Rút gọn:

Answer 1

\(A=\dfrac{8^7\cdot9^{21}}{18^5\cdot6^7\cdot27^5}=\dfrac{2^{21}\cdot3^{42}}{2^{12}\cdot3^{32}}=2^9\cdot3^{10}\)

\(B=10\cdot\dfrac{4^6\cdot9^5+6^9\cdot120}{8^4\cdot3^{12}-6^{11}}=10\cdot\dfrac{2^{12}\cdot3^{10}+2^{12}\cdot3^{10}\cdot5}{2^{12}\cdot3^{12}-2^{11}\cdot3^{11}}\)

\(=10\cdot\dfrac{2^{13}\cdot3^{11}}{2^{11}\cdot3^{11}\cdot5}\)

\(=10\cdot2^2\cdot\dfrac{1}{5}=8\)