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수학동아 - 폴리매스
본문바로가기
함께 풀고 싶은 문제
창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.
[창의 퍼즐] 강
뉴_턴 2019.10.22 04:24 조회 753

물이 서쪽에서 동쪽으로 시속 30km/h로 흐르는 강이 있다. 이때, 강의 윗부분에서 정남쪽인 강의 한 지점에 배를 타고 시속 10km/h로 가려고 한다. 강은 윗쪽과 아랫쪽이 평행할때, 도착할 지점으로부터 서쪽으로 몇 km떨어진 지점에 있어야할까??

이 문제 어떠셨나요?

글쎄요

0

어려워요

0

  •  
    뉴_턴 Lv.8 2019.10.22 04:29

    힌트 : 백터

    댓글 작성하기 좋아요0 댓글수2
    •  
      code Lv.5 2019.10.22 05:14

      조건이 조금 모자라는 듯합니다..

      시속10이 의미하는 바가 뭔지 정확히 서술할 필요가 있어보입니다. 저 조건 그대로라면 배는 기울여진 상태로 강을 거스르며 y 10으로 가야합니다.

      여러 방향으로 해석해보았습니다만, 그럴 경우 항상 강의 거리가 필요했습니다.

      좋아요0
    •  
      뉴_턴 Lv.8 2019.10.22 05:59

      아!! 죄송합니다. 강 사이의 거리는 5km로 가정합니다.

      좋아요0
  •  
    H2O 물 Lv.5 2019.10.22 05:22

    제 프로필이랑 똑같네요..

    댓글 작성하기 좋아요0 댓글수2
  •  
    집고양이 Lv.8 2019.10.22 07:48 비밀댓글
    확인요청중
    비밀 댓글이 등록 되었습니다.
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    •  
      집고양이 Lv.8 2019.10.22 07:49 비밀댓글
      비밀 댓글이 등록 되었습니다!
  •  
    해결
    집고양이 Lv.8 2019.10.22 07:51 비밀댓글
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