Question

ai giúp mình với ạ

 

Answer 1

Ta có: \(B=\dfrac{5\cdot4^{15}\cdot27^6-4^4\cdot3^{20}\cdot8^7}{15\cdot2^{10}\cdot6^{18}-7\cdot2^{29}\cdot9^9}\)

\(=\dfrac{5\cdot2^{30}\cdot3^{18}-2^8\cdot3^{20}\cdot2^{21}}{3\cdot5\cdot2^{10}\cdot2^{18}\cdot3^{18}-7\cdot2^{29}\cdot3^{18}}\)

\(=\dfrac{5\cdot2^{30}\cdot3^{18}-2^{29}\cdot3^{20}}{5\cdot3^{19}\cdot2^{28}-7\cdot2^{29}\cdot3^{18}}\)

\(=\dfrac{2^{29}\cdot3^{18}\left(5\cdot2-3^2\right)}{3^{18}\cdot2^{28}\left(5\cdot3-7\cdot2\right)}\)

\(=\dfrac{2\cdot\left(10-9\right)}{15-14}=2\)