Question

a) \(25^3:5^2\)

b) \(\left(\dfrac{3}{7}\right)^{21}:\left(\dfrac{9}{49}\right)^6\)

c) \(\dfrac{4^2.43}{210}\)

d) \(\dfrac{2^7.9^3}{6^5.8^2}\)

e) \(\dfrac{5^4.20^4}{25^5.4^5}\)

Mình cần gấp, mấy bạn cố gắng giải nhanh giúp mình nha. Thank you.^_^

Answer 1

a)625

b)3.338715722

c)344/155

d)3/16

e)1/100

/ là phần nghe

Answer 2

\(a,25^3:5^2=\left(5^2\right)^3:5^2=5^6:5^2=5^4\)

\(b,\left(\dfrac{3}{7}\right)^{21}:\left(\dfrac{9}{49}\right)^6=\)\(\left(\dfrac{3^{21}}{7^{21}}\right):\left(\dfrac{9^6}{49^6}\right)=\dfrac{3^{21}:7^{21}}{9^6:49^6}=\dfrac{3^{21}:7^{21}}{\left(3^2\right)^6:\left(7^2\right)^6}=\dfrac{3^{21}:7^{21}}{3^{12}:7^{12}}=3^9:7^9=\dfrac{3^9}{7^9}=\left(\dfrac{3}{7}\right)^9\)

\(c,\dfrac{4^2.43}{210}=\dfrac{\left(2^2\right)^2.43}{7.3.2.5}=\dfrac{2^4.43}{7.3.2.5}=\dfrac{2^3.43}{7.3.5}=\dfrac{344}{105}\)

\(d,\dfrac{2^7.9^3}{6^5.8^2}=\dfrac{2^7.\left(3^2\right)^3}{\left(2.3\right)^5.\left(2^3\right)^2}=\dfrac{2^7.3^6}{2^5.3^5.2^6}\) =\(\dfrac{2^7.3^6}{2^{11}.3^5}=\dfrac{3}{2^4}=\dfrac{3}{16}\)

Answer 3

=