Răspuns :
[tex] \frac{1}{ 4^{-2} } = \frac{1}{ \frac{1}{ 4^{2} } } = 1* 4^{2} = 4^{2}=16 [/tex]
[tex] \frac{1}{\frac{1}{4}^{2}} = \frac{1}{ \frac{1}{16}} = 16[/tex]