What is the surface area of a cone with a diameter of 5 and a height of 11?
回答 (2)
2016-06-01 8:52 pm
slant length ℓ = √(h²+r²)
= √(11²+2.5²)
≅ 11.28 cm
lateral area = πrℓ
= π(2.5)(11.28)
≅ 88.59 cm²
base area = πr²
= π2.5²
≅ 19.63 cm²
surface area ≅ 88.59 + 19.63 = 108.23 cm²
= √(11²+2.5²)
≅ 11.28 cm
lateral area = πrℓ
= π(2.5)(11.28)
≅ 88.59 cm²
base area = πr²
= π2.5²
≅ 19.63 cm²
surface area ≅ 88.59 + 19.63 = 108.23 cm²
2016-06-01 8:47 pm
A = π r (r + √(r² + h²))
r = d/2 = 5/2 = 2.5
h = 11
=> A = 3.1415926536 * 2.5 * (2.5 + √(2.5² + 11²))
= 108.2319
Answer : the surface area is 108.2319 .
r = d/2 = 5/2 = 2.5
h = 11
=> A = 3.1415926536 * 2.5 * (2.5 + √(2.5² + 11²))
= 108.2319
Answer : the surface area is 108.2319 .
收錄日期: 2021-04-21 18:54:17
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