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let R be the region bounded by y=x^2, x=1, y=0. Use the shell method to find the volume of the solid generated when R is revolved about the line y = -4

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To use the shell method, we need to integrate along the y-axis. The radius of each shell is y + 4, and the height of each shell is x. The limits of integration are y = 0 and y = 1.

The volume of the solid is given by:

V = 2π ∫[0,1] (y + 4) x dy

Using the equation y = x^2, we can express x in terms of y:

x = sqrt(y)

Substituting this into the integral, we get:

V = 2π ∫[0,1] (y + 4) sqrt(y) dy

We can simplify this integral by using u-substitution. Let u = y^(3/2), then du/dy = (3/2) y^(1/2) and dy = (2/3) u^(-2/3) du. Substituting these into the integral, we get:

V = 2π ∫[0,1] (y + 4) sqrt(y) dy
= 2π ∫[0,1] (u^(2/3) + 4) u^(-1/3) (2/3) du
= (4/3)π ∫[0,1] (u^(2/3) + 4) u^(-1/3) du

Integrating, we get:

V = (4/3)π [3u^(5/3)/5 + 12u^(2/3)/2] |_0^1
= (4/3)π [3/5 + 6]
= (22/5)π

Therefore, the volume of the solid generated by revolving R about the line y = -4 is (22/5)π cubic units.
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