plis jawab nomor 1 dan 2 yg di lingkar tu dan pakai cara jalannya

jawab

habis dibagi x - 3 
x -3 = 0
x = 3
f(3) = 0
(3)³ + p(3)² +9(3) +18 = 0
27 + 9p + 27 +18  = 0
9p + 72  =0
9p = -72
p = -72/9
p= -8

2)  f(x) =8x³ -18x² + px + 30
2x-3 =0
x = 3/2

f(3/2) = 0

8(3/2)³ -18(3/2)²+ p(3/2) + 30  = 0
8 (27/8) - 18(9/4) + 3p/2 + 30 = 0
27 - 40,5 + 3p/2 + 30 = 0

3/2 p = -16,5
p= -11