The volume of the solid obtained by rotating the region bounded by the curves x = 4y^2 - y^3 and x = 0 about the x-axis using the method of cylindrical shells is given by the integral:
V = 2π ∫[0,1] y(4y^2 - y^3) dy
Simplifying the integrand, we get:
V = 2π ∫[0,1] (4y^3 - y^4) dy
Integrating, we get:
V = 2π [(y^4 - (1/5)y^5)]|[0,1]
V = 2π [(1 - (1/5))] = (8/5)π
Therefore, the volume of the solid is (8/5)π cubic units.