Bạn chưa đăng nhập. Vui lòng đăng nhập để hỏi bài
Ẩn danh

Làm bài 10 câu từ câu 7 đến câu 15 

HT.Phong (9A5)
24 tháng 6 lúc 20:22

7) \(\dfrac{6^{15}\cdot9^{10}}{3^{34}\cdot2^{13}}=\dfrac{2^{15}\cdot3^{15}\cdot\left(3^2\right)^{10}}{3^{34}\cdot2^{13}}=\dfrac{2^{15}\cdot3^{35}}{3^{34}\cdot2^{13}}=2^2\cdot3=12\)

8) \(\dfrac{9^2\cdot2^{11}}{16^2\cdot6^3}=\dfrac{\left(3^2\right)^2\cdot2^{11}}{\left(2^4\right)^2\cdot2^3\cdot3^3}=\dfrac{3^4\cdot2^{11}}{2^{11}\cdot3^3}=3\)

9) \(\dfrac{4^5\cdot9^4}{8^3\cdot27^3}=\dfrac{\left(2^2\right)^5\cdot\left(3^2\right)^4}{\left(2^3\right)^3\cdot\left(3^3\right)^3}=\dfrac{2^{10}\cdot3^8}{2^9\cdot3^9}=\dfrac{2}{3}\)

10) \(\dfrac{27^4\cdot4^3}{9^5\cdot8^2}=\dfrac{\left(3^3\right)^4\cdot\left(2^2\right)^3}{\left(3^2\right)^5\cdot\left(2^3\right)^2}=\dfrac{3^{12}\cdot2^6}{3^{10}\cdot2^6}=3^2=9\)

11) \(\dfrac{3^{29}\cdot4^{16}}{27^9\cdot8^{11}}=\dfrac{3^{29}\cdot\left(2^2\right)^{16}}{\left(3^3\right)^9\cdot\left(2^3\right)^{11}}=\dfrac{3^{29}\cdot2^{32}}{3^{27}\cdot2^{33}}=\dfrac{3^2}{2}=\dfrac{9}{2}\)

Toru
24 tháng 6 lúc 20:27

7) \(\dfrac{6^{15}.9^{10}}{3^{34}.2^{13}}=\dfrac{\left(2.3\right)^{15}.\left(3^2\right)^{10}}{3^{34}.2^{13}}=\dfrac{2^{15}.3^{15}.3^{20}}{3^{34}.2^{13}}\)

\(=\dfrac{2^{15}.3^{35}}{3^{34}.2^{13}}=2^2.3=12\)

8) \(\dfrac{9^2.2^{11}}{16^2.6^3}=\dfrac{\left(3^2\right)^2.2^{11}}{\left(2^4\right)^2.\left(2.3\right)^3}=\dfrac{3^4.2^{11}}{2^8.2^3.3^3}\)

\(=\dfrac{2^{11}.3^4}{2^{11}.3^3}=3\)

9) \(\dfrac{4^5.9^4}{8^3.27^3}=\dfrac{\left(2^2\right)^5.\left(3^2\right)^4}{\left(2^3\right)^3.\left(3^3\right)^3}=\dfrac{2^{10}.3^8}{2^9.3^9}=\dfrac{2}{3}\)

10) \(\dfrac{27^4.4^3}{9^5.8^2}=\dfrac{\left(3^3\right)^4.\left(2^2\right)^3}{\left(3^2\right)^5.\left(2^3\right)^2}=\dfrac{3^{12}.2^6}{3^{10}.2^6}=3^2=9\)

11) \(\dfrac{3^{29}.4^{16}}{27^9.8^{11}}=\dfrac{3^{29}.\left(2^2\right)^{16}}{\left(3^3\right)^9.\left(2^3\right)^{11}}=\dfrac{3^{29}.2^{32}}{3^{27}.2^{33}}\)

\(=\dfrac{3^2}{2}=\dfrac{9}{2}\)

12) \(\dfrac{4^{20}.3^{35}}{2^{37}.27^{12}}=\dfrac{\left(2^2\right)^{20}.3^{35}}{2^{37}.\left(3^3\right)^{12}}=\dfrac{2^{40}.3^{35}}{2^{37}.3^{36}}\)

\(=\dfrac{2^3}{3}=\dfrac{8}{3}\)

13) \(\dfrac{6^7.4^2}{9^2.12^5}=\dfrac{\left(2.3\right)^7.\left(2^2\right)^2}{\left(3^2\right)^2.\left(3.2^2\right)^5}=\dfrac{2^7.3^7.2^4}{3^4.3^5.2^{10}}\)

\(=\dfrac{2^{11}.3^7}{2^{10}.3^9}=\dfrac{2}{3^2}=\dfrac{2}{9}\)

14) \(\dfrac{15^2.9^3}{25^3.27^2}=\dfrac{\left(3.5\right)^2.\left(3^2\right)^3}{\left(5^2\right)^3.\left(3^3\right)^2}=\dfrac{3^2.5^2.3^6}{5^6.3^6}\)

\(=\dfrac{3^8.5^2}{5^6.3^6}=\dfrac{3^2}{5^4}=\dfrac{9}{625}\)

15) \(\dfrac{5^4.20^4}{25^5.4^5}=\dfrac{5^4.\left(5.2^2\right)^4}{\left(5^2\right)^5.\left(2^2\right)^5}=\dfrac{5^4.5^4.2^8}{5^{10}.2^{10}}\)

\(=\dfrac{5^8.2^8}{5^{10}.2^{10}}=\dfrac{1}{5^2.2^2}=\dfrac{1}{100}\)

HT.Phong (9A5)
24 tháng 6 lúc 20:26

12) \(\dfrac{4^{20}\cdot3^{35}}{2^{37}\cdot27^{12}}=\dfrac{\left(2^2\right)^{20}\cdot3^{35}}{2^{37}\cdot\left(3^3\right)^{12}}=\dfrac{2^{40}\cdot3^{35}}{2^{37}\cdot3^{36}}=\dfrac{2^3}{3}=\dfrac{8}{3}\)

13) \(\dfrac{6^7\cdot4^2}{9^2\cdot12^5}=\dfrac{2^7\cdot3^7\cdot\left(2^2\right)^2}{\left(3^2\right)^2\cdot4^5\cdot3^5}=\dfrac{2^7\cdot3^7\cdot2^4}{3^4\cdot\left(2^2\right)^5\cdot3^5}=\dfrac{2^{11}\cdot3^7}{3^9\cdot2^{10}}=\dfrac{2}{3^2}=\dfrac{2}{9}\)

14) \(\dfrac{15^2\cdot9^3}{25^3\cdot27^2}=\dfrac{5^2\cdot3^2\cdot\left(3^2\right)^3}{\left(5^2\right)^3\cdot\left(3^3\right)^2}=\dfrac{5^2\cdot3^2\cdot3^6}{5^6\cdot3^6}=\dfrac{3^2}{5^4}=\dfrac{9}{625}\)

15) \(\dfrac{5^4\cdot20^4}{25^5\cdot4^5}=\dfrac{5^4\cdot5^4\cdot4^4}{\left(5^2\right)^5\cdot\left(2^2\right)^5}=\dfrac{5^8\cdot\left(2^2\right)^4}{5^{10}\cdot2^{10}}=\dfrac{5^8\cdot2^8}{5^{10}\cdot2^{10}}=\dfrac{1}{5^2\cdot2^2}=\dfrac{1}{100}\)


Các câu hỏi tương tự
kawadesu koneko
Xem chi tiết
kawadesu koneko
Xem chi tiết
yuki judai
Xem chi tiết
đặng thùy dương 5H
Xem chi tiết
Thịnh Quang Huy
Xem chi tiết
Vương Tuấn Khải
Xem chi tiết
nguyen quynh anh
Xem chi tiết
NHAN NGUYEN THI
Xem chi tiết
nguyen quang huy
Xem chi tiết
Kẻ Bí Mật
Xem chi tiết