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Function: initBoardView

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수학동아 - 폴리매스
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함께 풀고 싶은 문제
나도 수학쌤 문장제 문제를 변형해 문제를 내는 곳입니다.
[문장제 문제&개념응용] 이런 코시 슈발
Scubed 2021.02.17 08:20 조회 476

a_1+2a_2+...+na_n=1

을 만족하는 수열에 대해 다음 식의 최솟값을 구하시오.

(a_1)^2+(a_2)^2+...+(a_n)^2+(a_1+a_2+...+a_n)^2

답은 n으로 표현됩니다.

이 문제 어떠셨나요?

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어려워요

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  •  
    Scubed Lv.7 2021.02.17 08:22

    Cauchy-Schwarz Inequality를 쓰시면 해결하실 수 있습니다(그냥 영어로 써봤어요).

    댓글 작성하기 좋아요0 댓글수2
    •  
      PF_ Lv.8 2021.02.17 18:57

      그 영어가 혹시...

      코시-슈바르츠 부등식 인가요?

      좋아요0
    •  
      Scubed Lv.7 2021.02.17 21:17

      네 맞아요

      좋아요0
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    다시 도전
    짱수학천재 Lv.7 2021.02.20 19:12 비밀댓글
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    •  
      Scubed Lv.7 2021.02.20 19:29 비밀댓글
      비밀 댓글이 등록 되었습니다!
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    짱수학천재 Lv.7 2021.02.20 19:31 비밀댓글
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