We have f(x) = x4 – 6x3 + 12x2 – 8x + 3
⇒ f'(x) = 4x3 – 18x2 + 24x – 8
⇒ f"(x) = 12x2 – 36x + 24
= 12(x2 – 3x + 2) = 12(x – 1)(x – 2)
Now, f"(x) = 0 gives x = 1, 2
when x = 1, y = 2
when x = 2, y = 3
Thus, the point of inflection are (1, 2) and (2, 3)