今天上数学课各种好玩的东西
于是就找到好多这个来分享一下
当然不是我写的
并且大部分的人好像只会去看第一个就不想看了
这篇关于数学上的悖论谬论的论证的文章是由北大中文系 Matrix67 所写,读来感觉很有意思,和大家一起分享,来一场头脑风暴
史上最经典的“证明” 设 a = b ,则 a·b = a^2 ,等号两边同时减去 b^2 就有 a·b - b^2 = a^2 - b^2
注意,这个等式的左边可以提出一个 b ,右边是一个平方差,于是有 b·(a - b) = (a + b)(a - b)
约掉 (a - b) 有 b = a + b
然而 a = b ,因此 b = b + b ,也即 b = 2b
约掉 b ,得 1 = 2
这可能是有史以来最经典的谬证了
Ted Chiang 在他的短篇科幻小说 Division by Zero 中写到: 引用 There is a well-known “proof” that demonstrates that one equals two
It begins with some definitions: “Let a = 1; let b = 1
” It ends with the conclusion “a = 2a,” that is, one equals two
Hidden inconspicuously in the middle is a division by zero, and at that point the proof has stepped off the brink, making all rules null and void
Permitting division by zero allows one to prove not only t