How can be 2+2=5

[imemilyalice 0]

Can anybody tell me about it?

Regards

 

Edited September 21, 2016 by bonanova
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[bonanova 83]

Spoiler

In normal number theory 2+2=4.

There is a "proof" for 2+2=5 just as there is a "proof" that 1=2. The puzzle is to spot their fallacies. In the former case, a negative square root is ignored (it assumes a particular square root has a positive value where the negative root applies) and in the other case division by zero is wrongly permitted.

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