TOLONG JAWAB,MAU UAS

12) a = 4
r = 2/4 = 1/2 = ½
Un = ar^n-1
Un = 4 • (½)^n-1 ( D )

13) f(x) = px + q
f(1) = p + q = 4
f(-2) = - 2p + q = 1
--------------------------(-)
3p = 3
p = 1
subtitusi
p + q = 4
1 + q = 4
q = 4 - 1
q = 3
nilai p = 1 dan q = 3 ( B )