tìm giá trị của biểu thức sau

a) 45 mũ 10 . 5 mũ 20 / 75 mũ 15

b) (0,8) mũ 5 / (0,4) mũ 6

c) 2 mũ 15 . 9 mũ 4 / 6 mũ 6 . 8 mũ 3

bài làm là:

a) 45^10.5^20/75 ^ 15

=(5.9)^10.5^20/(5.15)^15

=5^10.9^10.5^20/5^15.15^15

=5^30.3^20/5^15.3^15.5^15

=5^30.3^20/5^30.3^15

=5^30.3^20/5^30.3^15

=3^5

=243

mấy ý kia mình chia tính được ....A,hihi

45^10*5^20/75^15

=5^10*9^10*5^20/(5^2)^15

=5^10*5^20*9^10/5^30

=9^10

(0.8)^5/(0.4)^6

=(0.4)^5*2^5/(0.4)^6

=2^5/(0.4)

=32/(0.4)

=80

2^15*9^4/6^6*8^3

=2^15*(3^2)^4/2^6*3^6*(2^3)^3

=2^15*3^8/2^6*3^6*2^9

=3^2

=9

tick đúng nha

a) \(=\frac{\left(3.15\right)^{10}.5^5.5^{15}}{75^5}=\frac{15^5.5^5.3^{10}.15^5.5^{15}}{75^5}=\frac{\left(15.5\right)^5.\left(15.5\right)^{15}.3^{10}}{75^5}=\frac{75^{20}.3^{10}}{75^5}=75^{15}.3^{10}\)

b) \(\frac{2^{15}.9^4}{9^4.9^2.\left(2^3\right)^3}=\frac{2^9.9^4}{2^9.9^4.9^2}=\frac{1}{81}\)

a) A = \(\frac{45^{10}.5^{10}}{75^{10}}=\frac{\left(5.3^2\right)^{10}.5^{10}}{\left(5^2.3\right)^{10}}=\frac{5^{10}.3^{20}.5^{10}}{5^{20}.3^{10}}=\frac{5^{20}.3^{10}}{5^{20}}=3^{10}=59049\)

b) B = \(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(0,2.2^2\right)^5}{\left(0,2.2\right)^6}=\frac{\left(0,2\right)^5.2^{10}}{\left(0,2\right)^6.2^6}=\frac{2^4}{0,2}=\frac{16}{0,2}=80\)

c) C = \(\frac{2^{15}.9^4}{6^6.8^3}=\frac{2^{15}.\left(3^2\right)^4}{\left(2.3\right)^6.\left(2^3\right)^3}=\frac{2^{15}.3^8}{2^6.3^6.2^9}=\frac{2^{15}.3^2}{2^{15}}=3^2=9\)

\(A=\frac{\left(9^{10}×5^{10}×5^{10}\right)}{\left(25^{10}×3^{10}\right)}\)

\(A=\frac{\left(3^{20}×5^{20}\right)}{\left(5^{20}×3^{10}\right)}\)

\(A=\frac{3^{20}}{3^{10}}\)

\(A=3^{10}\)

a.

\(\frac{45^{10}\times5^{20}}{75^{15}}=\frac{\left(3^2\times5\right)^{10}\times5^{20}}{\left(3\times5^2\right)^{15}}=\frac{3^{20}\times5^{10}\times5^{20}}{3^{15}\times5^{30}}=3^5=243\)

b.

\(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(0,8\right)^5}{\left(0,4\right)^5}\times\frac{1}{\left(0,4\right)}=\left(\frac{0,8}{0,4}\right)^5\times\frac{1}{\frac{4}{10}}=2^5\times\frac{5}{2}=2^4\times5=16\times5=80\)

c.

\(\frac{2^{15}\times9^4}{6^6\times8^3}=\frac{2^{15}\times\left(3^2\right)^4}{\left(2\times3\right)^6\times\left(2^3\right)^3}=\frac{2^{15}\times3^8}{2^6\times3^6\times2^9}=3^2=9\)

Chúc bạn học tốt ^^

ta có \(\frac{45^{10}.5^{20}}{75^{15}}=\frac{\left(3^2.5\right)^{10}.5^{20}}{\left(5^2.3\right)^{15}}=\frac{3^{20}.5^{10}.5^{20}}{5^{30}.3^{15}}=3^5=243\)

hậu quả của việc chép sai đề là đây : mỏi tay , nhức óc , lại còn k đc ****