Use the second derivative to determine the point of inflection for y = x3 – x2 – 8x + 12. ????

Answer 1

y' = 3x^2 - 2x - 8
y '' = 6x - 2

at the point of inflection y'' = 0
6x-2 = 0
x = 2/6 = 1/3

if x=1/3
y = 1/27 - 1/9 - 8/3 + 12
= 250/27

the point of inflection is (1/3 , 250/27)