Bài 3:
a: \(\dfrac{11\cdot3^{22}\cdot3^7-9^{15}}{\left(2\cdot3^{14}\right)^2}=\dfrac{11\cdot3^{29}-3^{30}}{2^2\cdot3^{28}}=\dfrac{3^{29}\left(11-3\right)}{2^2\cdot3^{28}}=3\cdot\dfrac{8}{4}=3\cdot2=6\)
b: \(\dfrac{2^{10}\cdot3^{10}-2^{10}\cdot3^9}{2^9\cdot3^{10}}=\dfrac{2^{10}\cdot3^9\left(3-1\right)}{2^9\cdot3^{10}}=\dfrac{2}{3}\cdot2=\dfrac{4}{3}\)
c: \(\dfrac{4^5\cdot9^4-2\cdot6^9}{2^{10}\cdot3^8+6^8\cdot20}\)
\(=\dfrac{2^{10}\cdot3^8-2^{10}\cdot3^9}{2^{10}\cdot3^8+2^{10}\cdot3^8\cdot5}\)
\(=\dfrac{2^{10}\cdot3^8\left(1-3\right)}{2^{10}\cdot3^8\left(1+5\right)}=\dfrac{-2}{6}=-\dfrac{1}{3}\)
Bài 5:
a: \(\dfrac{15\cdot4^{12}\cdot9^7-4\cdot3^{15}\cdot8^8}{19\cdot2^{24}\cdot3^{14}-6\cdot4^{12}\cdot27^5}\)
\(=\dfrac{2^{24}\cdot3^{15}\cdot5-2^{26}\cdot3^{15}}{19\cdot2^{24}\cdot3^{14}-2^{25}\cdot3^{16}}\)
\(=\dfrac{2^{24}\cdot3^{15}\left(5-2^2\right)}{2^{24}\cdot3^{14}\left(19-2\cdot3^2\right)}=3\)
b: \(\dfrac{3^{15}\cdot2^{22}+6^{16}\cdot4^4}{2\cdot9^9\cdot8^7-7\cdot27^5\cdot2^{23}}\)
\(=\dfrac{3^{15}\cdot2^{22}+3^{16}\cdot2^{16}\cdot2^8}{2\cdot3^{18}\cdot2^{21}-7\cdot3^{15}\cdot2^{23}}\)
\(=\dfrac{3^{15}\cdot2^{22}\left(1+3\cdot2^2\right)}{3^{15}\cdot2^{22}\left(3^3-7\cdot2\right)}=1\)
c: \(\dfrac{16^3\cdot3^{10}+120\cdot6^9}{4^6\cdot3^{12}+6^{11}}\)
\(=\dfrac{2^{12}\cdot3^{10}+2^3\cdot3\cdot5\cdot2^9\cdot3^9}{2^{12}\cdot3^{12}+2^{11}\cdot3^{11}}\)
\(=\dfrac{2^{12}\cdot3^{10}\left(1+5\right)}{2^{11}\cdot3^{11}\left(2\cdot3+1\right)}=\dfrac{2}{3}\cdot\dfrac{6}{7}=\dfrac{12}{21}=\dfrac{4}{7}\)
cứu cứu xong tui tăng sp cho
