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pro3182001

ta có$15^{40}$<$16^{40}$=$2^{4.40}$=$2^{160}$<$2^{161}$
\Rightarrow$15^{40}$<$2^{161}$
 
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pro3182001

bạn có thể tham khảo cách này
Ta có $2^{91}$=$2^{13.7}$=$8192^{7}$
$5^{35}$=$5^{5.7}$= $3125^{7}$
\Rightarrow $8192^{7}$>$3125^{7}$
\Rightarrow $2^{91}$ > $5^{35}$
 
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pro3182001

bạn có thể tham khảo cách này
Ta có
$5^{217}$>$4^{217}$=$2^{217.2}$=$2^{434}$
$119^{72}$<$128^{72}$=$2^{72.5}$=$2^{360}$
\Rightarrow$2^{434}$>$2^{360}$
\Rightarrow$5^{217}$>$119^{72}$
 
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lamdetien36

Câu d:
$107^{50} < 125^{50} = (5^3)^{50} = 5^{150} = 5^{75}.5^{75}$
$73^{75} > 50^{75} = 5^{75}.10^{75} = 5^{75}.5^{75}.2^{75}$
Suy ra $73^{75} > 107^{50}$
​
 
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