1.25. y = 8x – 5/x4 + 1/x – 5√x4.
25 y`=(8x–5·x–4+1·x–1–x4/5)`= =8–5·(–4)x–5+1·(–1)·x–2–(4/5)x(4/5)–1= =8+(20/x5)–(1/x5)–(4/(5·x1/5))