# Proof that the squareroot of -i is 17.Watch

This discussion is closed.
16 years ago
#21
(Original post by Ben.S.)
(-1)^(1/2) is denoted as 'i'. It doesn't exist, but is damn useful!

Ben
I know about i. It was a typo, I meant to say, sqrt(-i) = 1...
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16 years ago
#22
(Original post by fishpaste)
Programming convention uses !=
... So why is that relevant to your proof?
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#23
(Original post by ZJuwelH)
... So why is that relevant to your proof?
Because the notation doesn't change the logic.
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16 years ago
#24
(Original post by ZJuwelH)
I know about i. It was a typo, I meant to say, sqrt(-i) = 1...
Oh, sorry. Wouldn't that be to say that -i = 1?

Ben
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16 years ago
#25
(Original post by ZJuwelH)
... So why is that relevant to your proof?
hes just mucking around - basically saying x doesn't equall y, and y doesn't equall z therefore x=z.
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#26
(Original post by It'sPhil...)
hes just mucking around - basically saying x doesn't equall y, and y doesn't equall z therefore x=z.
And so, I conclusively prove that everybody on this messageboard = bumblebees.
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16 years ago
#27
(Original post by fishpaste)
And so, I conclusively prove that everybody on this messageboard = bumblebees.
*Buzzzzz
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16 years ago
#28
(Original post by Ben.S.)
Oh, sorry. Wouldn't that be to say that -i = 1?

Ben
Yeah exactly, ain't that right?
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16 years ago
#29
(Original post by ZJuwelH)
Yeah exactly, ain't that right?
The modulus of -i in the Argand plane is 1, certainly. I don't know if this allows you to say that -i = 1. Actually, I'm quite sure that it doesn't.

Ben
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16 years ago
#30
QUITE EASY TO FIND

set (a+ib)^2=-i

open brackets. for two complex numbers to be equal their real and complex parts must be eqaul. so u get two simulteneous equations for a and b . solving for real a and b . as a and b are difined as real. we get

a = -1/root2 and b = 1/root

there the the square root of -iisnt 17

its -1/root2 +(1/root2)i
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16 years ago
#31
something does not equal something else does not imply something equals something else entirely given something else does not equal something else entirely fullstop

(i might be able to give you this in symbolic notation if i had a scanner right now.)
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16 years ago
#32
(Original post by fishpaste)
squareroot of -i = (-i)^1/2 = 1 + (-i)^1/2 - 1 != 2, since 2^2 = 4 != -i.

Now 2 != 17

=> (-i)^1/2 = 17.
This was the most silly derivation Ive seen! You just treated an inequality as an equation. here you have an equally silly derivation which follows the same pattern:

3 is not equal to 4

5 is not equal to 4

Thus 3 is equal to 5.

It doesnt take a genious to see why this, and consequently your, equation is incorrect.
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16 years ago
#33
(Original post by Jonatan)
This was the most silly derivation Ive seen! You just treated an inequality as an equation. here you have an equally silly derivation which follows the same pattern:

3 is not equal to 4

5 is not equal to 4

Thus 3 is equal to 5.

It doesnt take a genious to see why this, and consequently your, equation is incorrect.
that is what i was trying to say (albeit in a slightly longwinded way)
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16 years ago
#34
(Original post by elpaw)
that is what i was trying to say (albeit in a slightly longwinded way)
Oh, sorry , I didnt really bother to read teh replies...

From now on I think Im just going to ignore these threads...
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16 years ago
#35
(Original post by Jonatan)
Oh, sorry , I didnt really bother to read teh replies...

From now on I think Im just going to ignore these threads...
what you said was worth it (because my thing just didn't make any sense)
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16 years ago
#36
(Original post by elpaw)
what you said was worth it (because my thing just didn't make any sense)

Im going to ignore this thread starting NOW!
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16 years ago
#37
(Original post by elpaw)
what you said was worth it (because my thing just didn't make any sense)
"hes just mucking around - basically saying x doesn't equall y, and y doesn't equall z therefore x=z." was better
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16 years ago
#38
(Original post by Linda)
"hes just mucking around - basically saying x doesn't equall y, and y doesn't equall z therefore x=z." was better
Humpf, my own girlfriend tries to discredit my post...

Starting NOW!
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16 years ago
#39
i always find it funny the way that you guys take a joke seriously and bother writing proper posts to show that the 'proof' etc. (ie joke) is wrong.
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16 years ago
#40
right, just to clear up this debate......... the answer to EVERYTHING is 42

so you're all wrong
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