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[창의 퍼즐] 등차수열의 합 공식
은총알 2019.10.06 02:17 조회 611
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페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

등차수열은 1,2,3,4,5,6,7,8,9,10...처럼 이전 항에 차례로 일정한 값을 더하여 만들어진 수열을 등차수열이라고 한다. 그리고 등차수열에서 서로 이웃하는 두 항의 차를 공차라고 한다. 등차수열의 처음 수를 a ,공차를 d라고 할 때

등차수열의 첫번째 항부터 n번째 항까지의 합 공식을 구하고, 그 이유를 설명해라.

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  •  
    은총알 Lv.11 2019.10.06 02:17

    비댓, 정답확인요청은 필수!

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    동호 Lv.5 2019.10.06 03:43 비밀댓글
    확인요청중
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      은총알 Lv.11 2019.10.06 05:36 비밀댓글
      비밀 댓글이 등록 되었습니다!
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    K→C≡N Lv.11 2019.10.06 04:28 비밀댓글
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      은총알 Lv.11 2019.10.06 05:37 비밀댓글
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    부분해결
    유한의끝도못본남자 Lv.7 2019.10.06 09:29 비밀댓글
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      은총알 Lv.11 2019.10.06 19:38 비밀댓글
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    부분해결
    아인수타인 Lv.12 2020.01.25 00:45 비밀댓글

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