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수학동아 - 폴리매스
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[수학 정보] 허접해 보이는 로지컬
Amath 2021.12.03 07:22 조회 487

\frac{1}{\sqrt{-1}}=\frac{\sqrt{1}}{\sqrt{-1}}=\sqrt{\frac{1}{-1}}=\sqrt{-1}이다. 

 

그래서 \frac{1}{\sqrt{-1}}=\sqrt{-1}, 1=(\sqrt{-1})^{2}=-1

 

따라서 1=-1이다. 

 

 

등식의 성질을 이용하면, 모든 수가 같아진다. 

 

그래서, 모든 수는 같다. 

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