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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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Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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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

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Function: mkdir

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/Contents.php
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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

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Function: parseLatexImg

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Function: require_once

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Function: mkdir

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/Contents.php
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Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: getLatexImg

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Line: 585
Function: parseLatexImg

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Line: 425
Function: initBoardView

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

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[수학 정보] 코시슈바르츠 부등식의 증명
뉴_턴 2020.11.29 23:29 조회 710

A=a_{1}^{2}+a_{2}^{2}+..............+a_{n}^{2} , B=b_{1}^{2}+b_{2}^{2}+............+b_{n}^{2} 이라고하면,

2=1+1=\frac{a_{1}^{2}+a_{2}^{2}+....+a_{n}^{2}}{A}+\frac{b_{1}^{2}+b_{2}^{2}+........+b_{n}^{2}}{B}=(\frac{a_{1}^{2}}{A}+\frac{b_{1}^{2}}{B})+(\frac{a_{2}^{2}}{A}+\frac{b_{2}^{2}}{B})+........+(\frac{a_{n}^{2}}{A}+\frac{b_{n}^{2}}{B})\geq \frac{2a_{1}b_{1}}{\sqrt{AB}}+\frac{2a_{2}b_{2}}{\sqrt{AB}}+.......+\frac{2a_{n}b_{n}}{\sqrt{AB}}이다

이때, 양변에 \frac{\sqrt{AB}}{2}를 곱하고 제곱하면  증명이 된다 (단, 이 증명은 AB\neq 0일때의 증명이고, AB=0 이면a_{n}b_{n}=0 이므로 증명이 성립한다)

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