Point P moves along the curve y=2X^3 -12X^2 +X +9. Find the coordinates of P such that the normal to the curve at P will have a gradient that is either a maximum or minimum.
Please help with this question. TIA

Point P moves along the curve y=2X^3 -12X^2 +X +9. Find the coordinates of P such that the normal to the curve at P will have a gradient that is either a maximum or minimum.
Please help with this question. TIA