Question

So sanh 3⁹⁹ va 11²¹

Answer 1

3^39 va 11^21

3^39 < 3^42, 3^42=3^6.7=(3^6)^7=729^7

11^21=11^3.7=(11^3)^7=1331^7

vì 729^7 < 1331^7 nên 3^42 < 11^21

=> 3^39 < 11^21

Answer 2

Ta có :

\(3^{39}< 3^{42}=\left(3^2\right)^{21}=9^{21}\)

\(\Rightarrow9^{21}< 11^{21}\) \(\Rightarrow3^{99}< 11^{21}\)