Jika akar-akar persamaan kuadrat 2x² + 6x + 3 = 0 adalah p dan q maka (p + q) - pq = . . . .

2x² + 6x + 3 = 0
a = 2
b = 6
c = 3

p + q = -b/a
p + q = -6/2
p + q = -3

pq = c/a
pq = 3/2

(p + q) - pq
= -3 - 3/2
= -6/2 - 3/2
= -9/2 = -4 1/2