5. y = 4ˣ - x⁻⁴

5. $$y = 4^x - x^{-4}$$

$$y' = (4^x - x^{-4})' = 4^x \ln 4 - (-4)x^{-5} = 4^x \ln 4 + 4x^{-5}$$

Ответ: $$4^x \ln 4 + 4x^{-5}$$