6 2 х 6 2
------ - ---------- - ------- = -------------- - -----------
4х-х2 х2+4х х2-16 4(-1)-(-1)2 (-1)2+4(-1)
-1 6 2 -1 1 6 2
- --------- = -------- - ------- - -------- = - ---- - --- + ---
(-1)2-16 -4-1 1-4 1-16 15 5 3
1 18 10 9 3
- ---- = - ----- + ------- - ----- = - ------
15 15 15 15 5