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수학동아 - 폴리매스
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[잡담] 그냥 수학숙제하다 알게된거
222 2021.11.24 07:32 조회 296
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페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

원뿔의 옆넓이는 전개도로 구할 필요가 없고

그냥 반지름*모선*\pi 하시면 됩니다 (증명은 귀찮으니 생략)

따라서 원뿔의 겉넓이는 반지름(반지름+모선)\pi 가 되겠네요

(잡담에 쓸 가치도 없었네요)

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