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If a sector with a radius of 15cm and a central angle of 216 degrees forms the side of the cone, then the height of the cone is? R can be calculated by R / 15 * 360 = 216 If a sector with a radius of 15cm and a central angle of 216 degrees surrounds the side of the cone, then the height of the cone is? R can be calculated by R / 15 * 360 = 216. Why can it be calculated in this way? If it is a formula, write the formula
The arc length of the sector is the center angle * radius, which is also the circumference of the bottom circle, i.e
15 * 216 ° = 2 π r r is the radius of the bottom circle
15 * 216 ° = 360 ° * r is the above formula after deformation
The height of the cone is h = under the root sign (the square of 15 - the square of R)
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