[(\frac{1}{5 \sqrt{5} })^{ \frac{2}{3} } +25 ^{-0.25} ]*[(\frac{1}{5 \sqrt{5} })^{ \frac{2}{3} } -25 ^{-0.25} ]=
[{(\frac{1}{5\sqrt5})^{\frac{2}{3}}}]^2-(25^{-0,25})^2=
(\frac{1}{25*5})^{\frac{2}{3}}-(5^2)^{-0,5}=
(\sqrt[3]{\frac{1}{125}})^2-5^{-1}=(\sqrt[3]{(\frac{1}{5})^3})^2-5^{-1}=
(\frac{1}{5})^2-\frac{1}{5}=\frac{1}{25}-\frac{5}{25}=-\frac{4}{25}
wzór skróconego mnożenia
(a+b)(a-b)=a^2-b^2