bantu jawab ya... pake caranya ya...

PK ; 2x^2 + 6x + 3 = 0
x1 + x2 = -6/2 = -3
x1.x2 = 3/2
misal PK baru akar-akarnya a ,dan b. dengan a = x1+x2 dan b = x1.x2
a + b = x1 + x2 + x1.x2
a + b = -3 + 3/2
a + b = -6/2 + 3/2
a + b = -3/2
a.b = (x1+x2).x1.x2
a.b = (-3).(3/2)
a.b = -9/2
PK dimaksud : x^2 - (a+b) + a.b = 0
x^2 - -3/2 - 9/2 = 0
x^2 + 3/2 - 9/2 = 0
2x^2 + 3x - 9 = 0