[tex](\dfrac{2}{5} )^{7} \cdot (2,5)^{6} = (\dfrac{2}{5} )^{7} \cdot (2\frac{1}{2} )^{6} =(\dfrac{2}{5} )^{7} \cdot (\dfrac{5}{2} )^{6}= (\dfrac{2}{5} )^{7} \cdot (\dfrac{2}{5} )^{-6}=(\dfrac{2}{5} )^{7+(-6)} =(\dfrac{2}{5} )^{7-6} =(\dfrac{2}{5} )^{1} =\dfrac{2}{5}[/tex]
korzystam ze wzorów:
[tex]x^{-n} =(\frac{1}{x} )^{n} \\\\x^{n} \cdot x^{m} =x^{n+m}[/tex]
