s*******e 发帖数: 1199 | 1 square root of -36 is 6i
square root of -4 is 2i
square root of -36 times square root of -4 is square root of -36x-4=144,
which is 12.
but 6ix2i=-12. So I proved 12=-12. |
t**s 发帖数: 483 | 2 hehe
【在 s*******e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : square root of -36 is 6i : square root of -4 is 2i : square root of -36 times square root of -4 is square root of -36x-4=144, : which is 12. : but 6ix2i=-12. So I proved 12=-12.
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S******u 发帖数: 743 | 3 不知道啊
【在 s*******e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : square root of -36 is 6i : square root of -4 is 2i : square root of -36 times square root of -4 is square root of -36x-4=144, : which is 12. : but 6ix2i=-12. So I proved 12=-12.
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h***o 发帖数: 5030 | 4 这么简单的问题还用得着虚数
我在公共版面要保持谦和作风
【在 s*******e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : square root of -36 is 6i : square root of -4 is 2i : square root of -36 times square root of -4 is square root of -36x-4=144, : which is 12. : but 6ix2i=-12. So I proved 12=-12.
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w********r 发帖数: 8704 | 5 square root of -36 is +/-6i
【在 s*******e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : square root of -36 is 6i : square root of -4 is 2i : square root of -36 times square root of -4 is square root of -36x-4=144, : which is 12. : but 6ix2i=-12. So I proved 12=-12.
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i****x 发帖数: 17565 | 6 你只证明了 -12^2 = 12^2,反过来是不对的。
【在 s*******e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : square root of -36 is 6i : square root of -4 is 2i : square root of -36 times square root of -4 is square root of -36x-4=144, : which is 12. : but 6ix2i=-12. So I proved 12=-12.
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h*x 发帖数: 674 | 7 以下wikipedia内容:
http://en.wikipedia.org/wiki/Square_root
(1)By convention, the principal square root of –1 is i
(2)For all non-negative real numbers x and y,
sqrt{xy} = sqrt{x} sqrt{y}
所以第三步有问题,对于负数,square root of -36 times square root of -4 is
NOT square root of -36x-4 |
s*****s 发帖数: 1509 | 8 square root of -36x-4=144,which is 12
。。。
小学生都知道144的平方根不止一个,是正负12。 |
x*****p 发帖数: 1707 | 9 Got the point!
【在 h*x 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 以下wikipedia内容: : http://en.wikipedia.org/wiki/Square_root : (1)By convention, the principal square root of –1 is i : (2)For all non-negative real numbers x and y, : sqrt{xy} = sqrt{x} sqrt{y} : 所以第三步有问题,对于负数,square root of -36 times square root of -4 is : NOT square root of -36x-4
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m********g 发帖数: 2323 | |
a********7 发帖数: 5325 | 11 你是你妈生的,你哥也是你妈生的,所以你就是你哥。 |
v*********n 发帖数: 3983 | 12 lol
how about 楼主是秦国的后代,苍井空是秦国的后代,所以他是苍井空?
【在 a********7 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 你是你妈生的,你哥也是你妈生的,所以你就是你哥。
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