Question

Va rog frumos 17,18!

Answer 1

17.d.
$7^{n-2 } \leq 343$ ⇒$7^{n-2} \leq 7^{3}$⇒
$n-2 \leq 3$⇒$n \leq 3+2$⇒$n \leq 5$
$n$∈{0,1,2,3,4,5}
18.b

$8^{17} = 2^{3*17} = 2^{51}$
16^12=2^4*12=2^48
2^51 >2^48
c.
27^13  si 9^20
27^13=3^3*13=3^39
9^20=3^2*20=3^40
3^39<3^40
d.
3^27 si 9^13
9^13=3^2*13=3^26
3^27>3^26