y= 1/12x^2
y'=1/6x
y'(6)=1
gradient of normal is -1/m
-1/1 = -1
use point gradient formula
y-3=x+6
y=x+9
solve simultaneuously to find where the normal meets the parabola
x+9=1/12x^2
x^2-12x-108=0
factorise to find the two places where it cuts the parabola
One answer will be (6,3)
The...