Answer:
12x^2 -21x -6
Step-by-step explanation:
(3x-6)(4x+1)
FOIL
first 3x*4x= 12x^2
outer 3x*1 = 3x
inner -6*4x = -24x
last -6*1 = -6
Add them together
12x^2 +3x -24x -6
Combine like terms
12x^2 -21x -6
X=2
Y=4
There are more than 1 solution
so f ' (x) = 0 and f ' ' (x) = 0 for the same x . so f '(x) = f '' (x)
f ' = 4x^3 + 2bx + 8 = f '' (x) = 12x^2 + 2b
