
Bobosharif S. answered 09/20/20
Tutor
4.4
(32)
PhD in Math, MS's in Calulus
We need to find such k that the following will hold
x2–x+k = (x–3)(ax+b)
x2–x+k = ax2+(b-3a)x-3b
From here it follows that (equate coefficients from both sides)
x2: a=1,
x: b-3a=-1
x0: k=-3b
==> a=1, b=2, k=-6
(x-3)(x+3)= x^2-x-6
So k=-6