수학동아 - 폴리매스

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함께 풀고 싶은 문제

창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.

[창의 퍼즐] 수동 91쪽 변형

아인수타인 2020.01.01 09:43 조회 723

문제 푼 사람 0명

페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

수학동아 2020년 1월호 91쪽 변형문제입니다.

수동 1월호 91쪽에서는 12km를 a의 길이로 가정하였다.

그런데 심장이 하늘에서 땅까지 진자운동하려면 (아직 수동을 안 보신 분들이 보시면 좀 섬뜩하게 볼 수도 있는데 보시면 절대 그렇지 않습니다!) 실질적으로 b의 길이가 12km여야 하지 않을까? 그러면 실의 길이 $l$ 은 최소 얼마가 되어야 할까? 또, $heta$ 를 60도 이하로 제한할 때 $l$ 은 최소 얼마가 되어야 할까?

이전글 새해 첫 문제! (새해 복 많이 받으세요~)

다음글 기호 ♡

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