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 2 years ago
Puzzle: Who can spot what is wrong here?
Theorem: 4 = 5
Proof: 20 = 20
16  36 = 25  45
4^2  (9x4) = 5^2  (9x5)
4^2  (9x4) + 81/4 = 5^2  (9x5) + 81/4
(4  9/2)^2 = (5  9/2)^2
4  9/2 = 5  9/2
4 = 5
 2 years ago
Puzzle: Who can spot what is wrong here? Theorem: 4 = 5 Proof: 20 = 20 16  36 = 25  45 4^2  (9x4) = 5^2  (9x5) 4^2  (9x4) + 81/4 = 5^2  (9x5) + 81/4 (4  9/2)^2 = (5  9/2)^2 4  9/2 = 5  9/2 4 = 5

This Question is Closed

lgbasallote
 2 years ago
Best ResponseYou've already chosen the best response.0how did you get 20=20 from 4=5

asnaseer
 2 years ago
Best ResponseYou've already chosen the best response.0The Theorem states 4 = 5 It is then followed by the proof

asnaseer
 2 years ago
Best ResponseYou've already chosen the best response.0and what exactly is wrong with that step?

Freyes
 2 years ago
Best ResponseYou've already chosen the best response.3The step is squaring a negative 1/2 and the other is squaring 1/2

asnaseer
 2 years ago
Best ResponseYou've already chosen the best response.0which is fine, since (1/2)^2 = (1/2)^2

Freyes
 2 years ago
Best ResponseYou've already chosen the best response.3Yes but then the square root of that after is where the problem is

Freyes
 2 years ago
Best ResponseYou've already chosen the best response.3you're choosing the positive side

Freyes
 2 years ago
Best ResponseYou've already chosen the best response.3not the same negative part you're squaring

asnaseer
 2 years ago
Best ResponseYou've already chosen the best response.0it is essentially the same as saying: (1)^2 = (1)^2 therefore 1 = 1

oldrin.bataku
 2 years ago
Best ResponseYou've already chosen the best response.0\[\pm[4\frac92]=\pm[5\frac92]\]
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