\(\frac{5^{11}.7^{12}+5^{11}.7^{10}}{5^{12}.7^{12}+9.5^{11}.7^{11}}=\frac{5^{11}7^{10}\left(7^2+1\right)}{5^{11}7^{11}\left(5.7+9\right)}=\frac{50}{7.44}=\frac{25}{154}\)

\(\frac{25^{14}.5^{10}.625^3.125^7}{5^{14}.125^{10}.25^3.625^7}=\frac{\left(5^2\right)^{14}.5^{10}.\left(5^4\right)^3.\left(5^3\right)^7}{5^{14}.\left(5^3\right)^{10}.\left(5^2\right)^3.\left(5^4\right)^7}=\frac{5^{28}.5^{10}.5^{12}.5^{21}}{5^{14}.5^{30}.5^6.5^{28}}\)

\(=\frac{5^{71}}{5^{78}}=\frac{1}{5^7}=\frac{1}{78125}\)

eo ơi đưa về lũy thừa của các số nguyên tố là xong      

\(\frac{27^2.15^3.125^{17}.10^{10}.3^8.512+1024.25^{28}.12^6.15^7}{125.6^{17}+625^{12}.6^{13}.125^2.25^5.16}\)

=\(\frac{3^6.3^3.5^3.5^{34}.2^{10}.5^{10}.3^8.2^9+2^{10}.5^{56}.3^6.2^{12}.3^7.5^7}{5^{63}.6^{17}+5^{48}.6^{13}.5^6.2^4}\)=\(\frac{3^{17}.5^{47}.2^{19}+2^{22}.5^{63}.3^{13}}{5^{63}.6^{17}+5^{48}.6^{13}.5^6.2^4}=\frac{3^{13}.5^{47}.2^{19}.3^4+2^{19}.5^{47}.3^{13}.2^3.5^{16}}{5^{54}.6^{13}.5^9+5^{54}.6^{13}.2^4}\)

=\(\frac{3^{13}.5^{47}.2^{19}\left(3^4+2^3.5^{16}\right)}{5^{54}.6^{13}\left(5^9+2^4\right)}=\frac{6^{13}.2^6.5^{47}\left(3^4+2^3.5^{16}\right)}{5^7.5^{47}.6^{13}\left(5^9+2^4\right)}=\frac{2^6\left(3^4+2^3.5^{16}\right)}{5^7\left(5^9+2^4\right)}\)

Bạn hãy tự giải nốt

\(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)

=\(\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(5.7+9\right)}\)

= \(\frac{8}{35+9}\)

= \(\frac{8}{44}\)

= \(\frac{2}{11}\)

Hai câu a) và b) bạn chỉ cần xem số mũ rồi trừ số mũ là xong 

\(c)\) \(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}=\frac{2^{10}.3^9\left(3-1\right)}{2^9.3^{10}}=\frac{2^{10}.3^9.2}{2^9.3^{10}}=\frac{2^{11}.3^9}{2^9.3^{10}}=\frac{2^2}{3}=\frac{4}{3}\)

\(d)\) \(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}=\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(5.7+9\right)}=\frac{8}{35+9}=\frac{8}{44}=\frac{2}{11}\)

Chúc bạn học tốt 

Ta có : 21^0.3^10−2^10.3^9/2^9.3^10
=> 2^10.(3^10−3^9)/2^9.3^10
=> 2^10.3/2^9.3^10
=> 2/3^9=2/19683

dòng đầu tiên là 

ta có 2^10

nhé

\(a,\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}=\frac{2^{10}.3^9\left(3-1\right)}{2^9.3^{10}}=\frac{2.2}{3}=\frac{4}{3}\)

\(b,\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}=\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(5.7+9\right)}=\frac{8}{44}=\frac{2}{11}\)

học tốt

a)

\(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}\)

\(=\frac{2^{10}.3^9\left(3-1\right)}{2^9.3^{10}}\)

\(=\frac{2.2}{3}\)

\(=\frac{4}{3}\)

b)

\(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}\)

\(=\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(5.7+9\right)}\)

\(=\frac{8}{35+9}\)

\(=\frac{8}{44}\)

\(=\frac{2}{11}\)

\(\frac{5^{11}\cdot7^{12}+5^{11}\cdot7^{11}}{5^{12}\cdot7^{11}+9\cdot5^{11}\cdot7^{11}}\)

=\(\frac{5^{11}\cdot\left(7^{12}+7^{11}\right)}{5^{11}\left(5\cdot7^{11}+9\cdot7^{11}\right)}\)

=\(\frac{7^{12}+7^{11}}{5\cdot7^{11}+9\cdot7^{11}}\)

=\(\frac{7^{11}\left(7+1\right)}{7^{11}\left(5+9\right)}\)

=\(\frac{8}{14}=\frac{4}{7}\)

Kết quả này chắc chắn là đúng đấy

=45 nha

olm duyet di

= 45

tích nha!!!..^.^

bằng \(\frac{2}{11}\)bn nhé