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수학동아 - 폴리매스
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함께 풀고 싶은 문제
창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.
[창의 퍼즐] 싸움
delta 2019.11.11 08:58 조회 645

v= \begin{bmatrix} cos t\\ sin t \end{bmatrix} 로 정의할 때

어느 학생은 하교를 하다가 놀이터에서 뛰어놀고 있는 아이들을 보았다.

그 학생은 인기가 없어서 놀 친구가 없어서 그 아이들이 부러웠다.

질투심에 그 학생은 싸움을 하기로 했다.

아이들은 총 4명이었고 놀이터의 이름은 내적 공간이었다.

아이들은 단위원에서 술래잡기를 하고 있었다.

학생은 먼저 이름을 물어봤는데

한명은 위치는 v였고

나머지 세명은 위치는 차례대로

\dot{v}, \ddot{v}, \dddot{v} 였다.

그 학생은 시간적 효율을 중시해서 싸움을 빨리 끝내고 싶어했다.

시간 t 는 항상 양의 방향으로 흐르고, 고딩이 시비를 걸 준비를 마쳤을 때에 t=0이었다.

그 학생은 힘을 숨긴 사람이라서 싸움을 \lim_{x\rightarrow 0}{x}초만에 끝낼 수 있다.

그 학생은 준비를 마쳤을 때 v와 같은 곳이 있었다.

학생은 방향을 바꾸지 않고 4연타로 아이들을 해치웠다.

그 학생은 단위원에서만 아이들과 같은 속력으로 움직여서

최소 시간에 아이들을 모두 해치웠다.

이때 고딩은 양의 방향으로 움직였을까. 아니면 음의 방향으로 움직였을까?

이 문제 어떠셨나요?

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0

어려워요

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  •  
    K→C≡N Lv.11 2019.11.11 15:15

    이름이 위치를 뜻하나요?

    어차피 삼각비 모르잖아

    댓글 작성하기 좋아요0 댓글수1
    •  
      delta Lv.7 2019.11.11 16:56

      네 이름은 위치를 뜻합니다

      좋아요0
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