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Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: file_put_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 202
Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: file_put_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Line: 315
Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 202
Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: initBoardView

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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 202
Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: initBoardView

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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: file_put_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: require_once

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Message: mkdir(): Permission denied

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 202
Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: initBoardView

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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: file_put_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: initBoardView

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once

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Message: mkdir(): Permission denied

Filename: libraries/Common.php

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 202
Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: initBoardView

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 213
Function: file_put_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 249
Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 131
Function: initBoardView

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once

개념 기사 기사 작성법
내가 아는 수학개념을 쉽게 설명해주세요!
[개념 기사] 근의 공식의 개념
Ljh 2022.06.23 04:54

<근의 공식의 개념>

ax^2+bx+c=0 이라는 식이 있을 때

x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}이다.

[증명]

ax^2+bx+c에서 a는 0이 아니므로 a로 나누면

x^2+\frac{b}{a}x+\frac{c}{a}=0이다.

c/a를 우변으로 이항하면

x^2+\frac{b}{a}x=-\frac{c}{a}이다. 여기에서 좌변을 완전제곱꼴로 만들려면 \frac{b^2}{4a^2}을 더해야 한다.

그러면 (x+\frac{b}{2a})^2=\frac{b^2-4ac}{4a^2}가 된다.

좌변의 제곱을 풀면 x+\frac{b}{2a}=\pm \frac{\sqrt{b^2-4ac}}{2a}가 되고

b/2a를 좌변으로 이항하면 드디어.....!!!!

x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}가 된다!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

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Backtrace:

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/views/ver3/inc/article_view.php
Line: 90
Function: _error_handler

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
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Function: view

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Line: 315
Function: require_once

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Backtrace:

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/views/ver3/inc/article_view.php
Line: 90
Function: _error_handler

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Article.php
Line: 221
Function: view

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once

수학동아 기자의 한마디
수학동아 기자 2022.08.17
근의 공식의 개념을 기사 형식으로 작성해서 올려주면 좋을 것 같습니다. 지금은 증명 과정만 올라와 있어서 기사라고 보기는 조금 어렵네요
이 기사 어떠셨나요?

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