Help : Proof that 2 = 1

Let aa and bb are two numbers such that a=b=2a = b = 2.

Therefore a2=aba^2 = ab [multiplying aa on both sides.]

a2b2=abb2a^2 - b^2 = ab - b^2 [subtracting b2b^2 on both sides.]

(a+b)(ab)=b(ab)(a + b)(a - b) = b(a-b)

(a+b)=b(a+b) = b

Now substituting the values of aa and bb , we get 2+2=22+2 = 2

Therefore 4=24 = 2 ?

#Algebra

Note by Rama Devi
5 years, 10 months ago

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1 vote

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Comments

you cannot cancel (a-b) on both sides because (a-b) =0 and division by 0 is not defined!

Raven Herd - 5 years, 10 months ago

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good observation

Sai Ram - 5 years, 10 months ago

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You are only 13 and you are level 5 in all subjects .Cool! Do you sit whole day at brilliant or you attempt every question correctly?

Raven Herd - 5 years, 10 months ago

You cannot cancel out (a-b). Think why?

Agnishom Chattopadhyay - 5 years, 10 months ago

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Because a - b is 0

Rama Devi - 5 years, 10 months ago
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