zad. 30 Oblicz (\frac{1}{7})^{-1} b) \frac{1}{(\frac{1}{7})^{-1}} c) (((\frac{1}{7})^{-1})^{-1})^{-1} d) (((\frac{1}{\frac{1}{7}})^{-1})^{-1})^{-1}
źródło: Matematyka z plusem;gimnazjum 2, zad 30 str 37
a) (\frac{1}{7})^{-1}=7^1=7 b) \frac{1}{(\frac{1}{7})^{-1}}=\frac{1}{7^1}=\frac{1}{7} c) (((\frac{1}{7})^{-1})^{-1})^{-1}=(\frac{1}{7})^{-1*(-1)*(-1)}=(\frac{1}{7})^{-1}=7^1=7 d) (((\frac{1}{\frac{1}{7}})^{-1})^{-1})^{-1}=7^{(-1)*(-1)*(-1)}=7^{-1}=\frac{1}{7}