A-maths~

根據偉達定理,
x1+x2= -b/a
x1‧x2=c/a

所以.....
α+α²= - (-12)/1
α+α²=12
α‧α²=k

解得........a=3
所以k=27

2007-07-03 21:48:04 補充：
sor......仲有一種就係a=-4所以a=-4,k=-64

consider α+α²=12----(1)
α x α²=k----(2)

From (1), α²+α-12=0
α=-4 or3

when α=-4, k=(-4)^3=-64
when α=3 , k=3^3=9