Giải thích các bước giải:
2/ a/ $25^{13}.125^7=(5^2)^{13}.(5^3)^7=5^{26}.5^{21}=5^{47}$
b/ $49^{48}:7^{94}=(7^2)^{48}:7^94=7^{96}:7^{94}=7^2$
c/ $(\dfrac{8}{27})^{41}.(\dfrac{4}{9})^{69}$
$=[(\dfrac{2}{3})^3]^{41}.[(\dfrac{2}{3})^2]^{69}$
$=(\dfrac{2}{3})^{123}.(\dfrac{2}{3})^{138}$
$=(\dfrac{2}{3})^{261}$
d/ $(\dfrac{25}{16})^{71}:(\dfrac{125}{64})^{20}$
$=[(\dfrac{5}{4})^2]^{71}:[(\dfrac{5}{4})^3]^{20}$
$=(\dfrac{5}{4})^{142}:(\dfrac{5}{4})^{60}$
$=(\dfrac{5}{4})^{82}$
3/ a/ $2^{500}=(2^5)^{100}=32^{100}$
và $5^{200}=(5^2)^{100}=25^{100}$
Vì $32^{100}>25^{100}$ nên $2^{500}>5^{200}$
b/ $2^{3333}=(2^3)^{1111}=8^{1111}$
và $3^{2222}=(3^2)^{1111}=9^{1111}$
Vì $8^{1111}<9^{1111}$ nên $2^{3333}<3^{2222}$
c/ $4^{2000}=(4^2)^{1000}=16^{1000}$
và $2^{4000}=(2^4)^{1000}=16^{1000}$
Vì $16^{1000}=16^{1000}$ nên $4^{2000}=2^{4000}$
d/ $99^{20}=(99^2)^{10}=9801^{20}$
Vì $9801^{20}<9999^{10}$ nên $99^{20}<9999^{10}$
Chúc bạn học tốt !!!