$a){\left(\frac{3}{8}\right)}^7<{\left(\frac{3}{8}\right)}^6$  

$b){\left(-0,4\right)}^{13}<{\left(-0,4\right)}^{15},\text{bo}{\left(-0,4\right)}^{13}=-{0,4}^{13}\text{oraz}{\left(-0,4\right)}^{15}=-{0,4}^{15}\text{i}{0,4}^{13}>{0,4}^{15}\text{stąd}-{0,4}^{13}<-{0,4}^{15}$ $b){\left(-0,4\right)}^{13}<{\left(-0,4\right)}^{15},\text{bo}{\left(-0,4\right)}^{13}=-{0,4}^{13}\text{oraz}{\left(-0,4\right)}^{15}=-{0,4}^{15}\text{i}{0,4}^{13}>{0,4}^{15}\text{stąd}-{0,4}^{13}<-{0,4}^{15}$  

$c){\left(\frac{11}{7}\right)}^{21}<{\left(\frac{11}{7}\right)}^{22}$  

$d){\left(\frac{8}{9}\right)}^{25}<{\left(\frac{9}{8}\right)}^{25}$  

$e)4^{-9}<4^{-8},\text{bo}{4}^{-9}=\frac{1}{4^9}\text{oraz}{4}^{-8}=\frac{1}{4^8}\text{i}\frac{1}{4^9}<\frac{1}{4^8}$  

$f){\left(\frac{5}{6}\right)}^{-16}>{\left(\frac{6}{5}\right)}^{-15},\text{bo}{\left(\frac{5}{6}\right)}^{-16}={\left(\frac{6}{5}\right)}^{16}\text{oraz}{\left(\frac{6}{5}\right)}^{-15}={\left(\frac{5}{6}\right)}^{15}\text{i}$   ${\left(\frac{6}{5}\right)}^{16}>{\left(\frac{5}{6}\right)}^{15}$