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Use cylindrical coordinates to find the volume of the solid.

solid inside
x2 + y2 + z2 = 16 and outside z =

x2 + y2

1 Answer

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The volume of the solid is 3578π/3.

Finding the Volume using Cylindrical Coordinates

Step 1: Define the region in cylindrical coordinates.

The solid is bounded by the sphere x^2 + y^2 + z^2 = 16 (radius 4) and the cone z = sqrt(x^2 + y^2).

In cylindrical coordinates, this region can be expressed as:

0 <= theta <= 2π

0 <= r <= 4

sqrt(r^2) <= z <= 16

Step 2: Set up the integral.

The volume element in cylindrical coordinates is: dV = r * dz * dr * dθ

We want to integrate over the defined region to find the total volume:

V = ∫(0 to 2π) ∫(0 to 4) ∫(sqrt(r^2) to 16) r dz dr dθ

Step 3: Evaluate the integral.

The first integration with respect to z is straightforward:

∫(sqrt(r^2) to 16) r dz = r(16 - sqrt(r^2))

The second integration with respect to r requires a substitution:

∫(0 to 4) r^2 (16 - sqrt(r^2)) dr = 256π/3 - 32π

Finally, the last integration is simple:

∫(0 to 2π) 256π/3 - 32π dθ = 3642π/3 - 64π

Step 4: Find the final volume.

V = 3642π/3 - 64π = 3578π/3

Therefore, the volume of the solid is 3578π/3.

User Meepmeep
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