\(=\left(\dfrac{0,8}{0,4}\right)^5\cdot\dfrac{1}{0,4}=2^5\cdot\dfrac{1}{0,4}=\dfrac{32}{0,4}=80\)

Giải:

\(\dfrac{\left(0,8\right)^5}{\left(0,4\right)^6}\)

= \(\left(\dfrac{0,8}{0,4}\right)^5.\dfrac{1}{0,4}\)

= \(2^5.\dfrac{1}{0,4}\)

= \(\dfrac{32}{0,4}=80\)

Hok tốt 

Tính giá trị biểu thức

\(\dfrac{2^{15}.9^4}{6^3.8^3}\)

Ta có: \(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}\)

\(=\frac{2^5\cdot\left(0,4\right)^5}{\left(0,4\right)\cdot\left(0,4\right)^5}=\frac{2^5}{0,4}=\frac{32}{0,4}=80\)

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 ^^

bang\(\frac{-1}{61}\)

Bằng 1/5 bạn ơi!

\(G=\frac{0,5+0,\left(3\right)-0,1\left(6\right)}{2,5+1,\left(6\right)-0,8\left(3\right)}\)\(=\frac{\frac{1}{2}+\frac{1}{3}-\frac{1}{6}}{\frac{5}{2}+\frac{5}{3}-\frac{5}{6}}\)\(=\frac{1}{5}.\left(\frac{\frac{1}{2}+\frac{1}{3}-\frac{1}{6}}{\frac{1}{2}+\frac{1}{3}-\frac{1}{6}}\right)\)\(=\frac{1}{5}.1=\frac{1}{5}\)