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use similar triangles and cross‑sectional area integration to find the formula for the volume of a right circular cone of height ℎ whose base is a circle of radius ℎ6.

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Final answer:

To find the formula for the volume of a right circular cone using similar triangles and cross-sectional area integration, we can start by considering a cone with height h and base radius r. We can create a similar triangle by drawing a line from the apex of the cone to a point on the base that is parallel to the height. Using the properties of similar triangles, we can derive the formula V = (πr²h³)/108 for the volume of the cone.

Step-by-step explanation:

To find the formula for the volume of a right circular cone using similar triangles and cross-sectional area integration, we can start by considering a cone with height h and base radius r.

We can create a similar triangle by drawing a line from the apex of the cone to a point on the base that is parallel to the height. This creates two similar triangles - the larger triangle represents the entire cone, and the smaller triangle represents the cross-section of the cone.

Since the smaller triangle is similar to the larger triangle, their corresponding sides are proportional. The height of the smaller triangle is h/6, and the base radius is r/6, which means the height of the larger triangle is h, and the base radius is r.

The formula for the area of the base of the cone is A = πr², so the area of the cross-section of the cone is (πr²)(h/6)² = πr²h²/36. This represents the differential volume element.

To find the total volume of the cone, we can integrate the differential volume element over the height of the cone from 0 to h. The integral becomes ∫[0,h] πr²h²/36 dh = πr²h³/108. Therefore, the formula for the volume of a right circular cone is V = (πr²h³)/108.

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