Graphing the curve and both tangents...

QUESTION:

(a) Find the slope of tangent to the curve y=3+4x^2-2x^3 at the point where x=a.

(b) Find equations of the tangent lines at the points (1,5) and (2,3).

(c) Graph the curve and both tangents on a common screen.

My answers:

(a) m(TL) = dy/dx = 8x-6x^2

(i) at P(1,5); m(TL) = 2

(ii) at P(2,3); m(TL) = -8

(b)

(i) y = 2x +3

(ii) y = -8x+19

(c) now in this part of graphing i don't know how to graph the curve since it is raised to cube..i don't know either what kind of curve is this..

^_^