tolong dijawab ya...yg pintar mtk

8)
v^6 (-2)^4 (v^12) = 16 v^18

9)
=(-a^-9) (-a^10) ( b^10)
=[(-a^10)(b^10)] / (-a)^9
=-a b^10

10)
3(-8)(m^-2)(m^-6)(m^4) n^2 = -24 m^-4 n^2

11)
r^4 r^15 r^8 s^6 s^12 = r^27 s^18

12)
[(a-b)^2  (a+b)^2] / [a (b^-1)  -  (a^-1)  b ]^2
= [(a-b)^2  (a+b)^2] / [a/b - b/a]^2
= [(a-b)^2  (a+b)^2] / [(a^2 / ab) - ( b^2 / ab)]^2
= [(a-b)^2  (a+b)^2] x [a^2 b^2] / [(a-b)^2  (a+b)^2]
= a^2 b^2