-1/4.5/7+4/7-18/13

=-5/28+4/7-18/13

=-5/28+16/28-18/13

=11/28-18/13

=-361/364

b)4.-7/12+5.17/15

=-7/3+17/3

=10/3

c)5^4.20^4/25^5.4^5

=625.160000/9765625.1024

=1/100

 = 5^4.5^4.4^4/(5^2)^5.4^5

 = 5^8.4^4/5^10.4^5

= 1/5^2.4 = 1/100

k mk nha

Ta có: \(\frac{5^4.20^4}{25^5.45}\)

=\(\frac{\left(5.20\right)^4}{\left(25.4\right)^5}\)

= \(\frac{100^4}{100^5}\)

=\(\frac{1}{100}\)

\(\frac{5^4\cdot20^4}{25^5\cdot4^5}=\frac{5^4\cdot5^4\cdot4^4}{5^5\cdot5^5\cdot4^5}=\frac{1}{100}\)

=\(\frac{100^4}{100^5}=100^{-1}=\frac{1}{100}\)

\(\frac{5^4.20^4}{25^5.4^5}=\frac{\left(5.20\right)^4}{\left(25.4\right)^5}=\frac{100^4}{100^5}=100^{-1}=\frac{1}{100}\)

\(\frac{5^4.20^4}{25^5.4^5}=\frac{5^4.\left(5.4\right)^4}{\left(5^2\right)^5.4^5}=\frac{5^4.5^4.4^4}{5^{10}.4^5}=\frac{5^{16}.4^4}{5^{10}.4^5}\)=\(\frac{5^6}{4}\)=\(\frac{3125}{4}\)

ủng hộ nha

\(\frac{5^4.20^4}{25^5.4^5}=\frac{5^4\left(1.15^4\right)}{\left(19^5.1\right).4^5}=\frac{5^4.15^4}{19^5.4^5}\)

\(\frac{5^4.20^4}{25^5.4^5}=\frac{\left(5.20\right)^4}{\left(25.4\right)^5}=\frac{100^4}{100^5}=\frac{1}{100}.\)

Chúc bạn học tốt!

\(\frac{5^4.20^4}{25^5.4^5}=\frac{5^4.\left(4.5\right)^4}{\left(5.5\right)^5.4^5}=\frac{5^4.4^4.5^4}{5^5.5^5.4^5}=\frac{5^8.4^4}{5^8.5^2.4^4.4}=\frac{1}{5^2.4}=\frac{1}{100}\)

\(\frac{5^4.20^4}{25^5.4^5}=\frac{5^4.5^4.4^4}{\left(5^2\right)^5.4^5}=\frac{5^8.4^4}{5^{10}.4^5}=\frac{1}{5^2.4}=\frac{1}{100}\)