Liczba  $\frac{5}{6}<1$  

a liczba:

  $\frac{6}{5}>1$  

zatem:

$1>{\left(\frac{5}{6}\right)}^{10}>{\left(\frac{5}{6}\right)}^{15}$ $1>{\left(\frac{5}{6}\right)}^{10}>{\left(\frac{5}{6}\right)}^{15}$  

`1< (6/5)^10  

$a>b$  

$c<d$  

`(5/6)^15  

zatem: 

$b<a<c<d$  


Odp. B