f''(x) = 12ex^2 \\ \\ \therefore f'(x) = \int 12ex^2 = 4ex^3+C
Now since the point (0,3) is a stationary point that means
f'(0) = 0 = 4e(0) + C \Rightarrow C = 0 \\ \\ \therefore f'(x) = 4ex^3
f(x) = \int 4ex^3 = ex^4 + C
since the point (0,3) exist on f(x), then
f(0) = 3 = e(0) + C...