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

\(\frac{45^{10}.5^{20}}{75^5}\)

\(=\frac{\left(3^2.5\right)^{10}.5^{20}}{\left(5^2.3\right)^5}\)

\(=\frac{3^{20}.5^{10}.5^{20}}{5^{10}.3^5}\)

\(=3^{15}.5^{20}\)

\(\frac{45^{10}.5^{20}}{75^5}=\frac{9^{10}.5^{10}.5^{20}}{25^5.3^5}=\frac{3^{20}.5^{10}.5^{20}}{5^{10}.3^5}=\frac{3^{20}.5^{30}}{5^{10}.3^5}=3^{15}.5^{20}\)

Bài 1:
a)

\(\frac{8^{20}+4^{20}}{4^{25}+64^5}=\frac{(2^3)^{20}+(2^2)^{20}}{(2^2)^{25}+(2^6)^{5}}=\frac{2^{60}+2^{40}}{2^{50}+2^{30}}=\frac{2^{40}(2^{20}+1)}{2^{30}(2^{20}+1)}=2^{10}\)

b)

\(\frac{45^{10}.5^{20}}{75^{15}}=\frac{(3^2.5)^{10}.5^{20}}{(3.5^2)^{15}}=\frac{3^{20}5^{30}}{3^{15}.5^{30}}=\frac{3^{20}}{3^{15}}=3^5\)

Bài 2:

Ta thấy $(x-2)^{2012}=[(x-2)^{1006}]^2\geq 0$ với mọi $x\in\mathbb{R}$

$|b^2-9|^{2014|\geq 0$ với mọi $b\in\mathbb{R}$ (tính chất trị tuyệt đối)

Do đó để tổng của chúng bằng $0$ thì:

\((x-2)^{2012}=|b^2-9|^{2014}=0\)

\(\Leftrightarrow \left\{\begin{matrix} x-2=0\\ b^2-9=0\end{matrix}\right.\Leftrightarrow \left\{\begin{matrix} x=2\\ b=\pm 3\end{matrix}\right.\)

Vậy.......

\(\frac{15^{10}.5^{10}}{75^{10}}\)

\(=\frac{15^{10}.5^{10}}{\left(15.5\right)^{10}}\)

\(=\frac{15^{10}.5^{10}}{15^{10}.5^{10}}\)

\(=1\)

          Bài làm :

Ta có :

\(\frac{15^{10}\times5^{10}}{75^{10}}=\frac{\left(15\times5\right)^{10}}{75^{10}}=\frac{75^{10}}{75^{10}}=1\)

\(75^{20}=45^{10}.5^{30}\)

\(45^{10}.5^{30}\)

=\(\left(3^2.5\right)^{10}.5^{10+20}\)

= \(\left(3^2\right)^{10}.5^{10}.5^{30}\)

= \(3^{20}.5^{40}\)

= \(3^{20}.\left(5^2\right)^{20}\)

= \(3^{20}.25^{20}\)

= \(75^{20}\)

cần giúp ko

Có, giúp mk với !

\(\frac{45^{10}20^{10}}{75^{15}}\)=\(\frac{1125^{10}}{75^5.75^{10}}\)=\(\frac{1125^{10}}{75}\)=\(\frac{1}{75^5}\)=\(\frac{15^{10}}{75^5}\)=\(\frac{15^5.15^5}{75^5}\)=\(\frac{15^5}{75}\).\(15^5\)=\(\frac{1^5}{3}\).\(15^5\)=\(\frac{1}{3}.15^5\)=\(^{5^5}\)=3125

Ta có : \(\frac{45^{10}.5^{20}}{75^{15}}=\frac{9^{10}.5^{10}.5^{20}}{3^{15}.25^{15}}=\frac{\left(3^2\right)^{10}.5^{30}}{3^{15}.\left(5^2\right)^{15}}=\frac{3^{20}.5^{30}}{3^{15}.5^{30}}=3^5\)

\(\frac{45^{10}.5^{20}}{75^{15}}=\frac{3^{20}.5^{10}.5^{20}}{3^{15}.5^{30}}=\frac{3^{20}.5^{30}}{3^{15}.5^{30}}=3^5=243\) 

   .Check mk nhá •<3 •