The volume V generated by rotating the region about y = −3 is 42π/5 cubic units.
The formula for volume using cylindrical shells is:
V = ∫ 2πrh * dx
In this case, we'll integrate with respect to y, as the curves are defined in terms of y. So, we have:
V = ∫ 2π(y^2 + 3)(y^2 + 3) dy
Determine the limits of integration:
The region is bounded by y = 0 and y = 1, so the limits of integration are:
V = ∫₀¹ 2π(y^2 + 3)(y^2 + 3) dy
Evaluate the integral:
V = 2π ∫₀¹ (y^4 + 6y^2 + 9) dy
V = 2π [(1/5)y^5 + 2y^3 + 9y]₀¹
V = 2π [(1/5) + 2 + 9] = 42π/5