Odpowiedź:
[tex]f(x)=\frac{1}{x}[/tex]
[tex]f'(x)=\frac{0-1}{x^2} =\frac{-1}{x^2}[/tex]
[tex]x_{0} =\frac{\sqrt{2} }{2}[/tex]
[tex]f'(x_{0})=f'(\frac{\sqrt{2} }{2})=\frac{-1}{(\frac{\sqrt{2} }{2})^2 } =\frac{-1}{\frac{2}{4} } =-1 \cdot \frac{4}{2} =-\frac{4}{2}[/tex]