# Prove That 1 is Equal to 2 in Four Different Methods

Let us prove that 1 is equal to 2. Is it possible? Can 1=2 ? Yes, possible theoretically. This is called Mathematical Fallacy. Here is the proof that 1 equals 2. So, What is Fallacy? It’s a statement or an argument based on false or invalid inference. In other words, it can described as certain kind of mistakes in calculation, derivation or proof that are often exhibited, collected, as illustrations of the concept of mathematical fallacy. These maths tricks can be sometimes very interesting and entertaining. In the below equations, we will assume that a=b for our calculation to prove that one is equal to 2.

Solution 2: To Prove 1=2 Using Addition and Subtraction method

Solution 3: To Prove 1=2 Using Multiplication and Substitution method

Solution 4: To Prove 1=2 Using Subtraction, Multiplication and Substitution method

Solution 5: To Prove 1=0.5

This is a bonus calculation to prove one is equal to half.

While discussing the above method with teja, one of my good friend,

He proved half is equal to one.

Using Division method.

rani

Oct 15. 2011

this is ridiculousness u cant divide by zero ::: a-b=0 ::

Babaji M P

Oct 20. 2011

How about ::: 5-5=0 :: ?

andy

Oct 15. 2011

you can not simplify with 0.if a=b then a-b=0 and therefore 1not equals 2

Babaji M P

Oct 20. 2011

Wait .. Multiply by 2 on both the sides !!!

Shinrya

Dec 13. 2011

if 5-5=0, that’s a no brainer. Then you say to multiply by 2 on both sides?? so 0=0? DUH.

Even 2(a-b)=2(0) wouldn’t work because anything multiplied by 0 is 0.

Dorald

Jan 05. 2012

in the first question you cant write (a+b)(a-b) because we dont know if b is positive or negative

Blob

Jan 12. 2012

It doesn’t matter if b is positive or negative, it will just switch the “+” to “-” and vice versa.

This makes no difference as (a+b)(a-b)=(a-b)(a+b) by rule of the Commutative (or something like that) Property of Multiplication, which states “a*b=b*a”.

Shahzad

Jan 10. 2012

Humm totally insane.. if for once a=b then why being so meany as not to consider a^2=b^2, and why write and treat “a” different than “b” in the solution later.. totally irrational..

Blob

Jan 12. 2012

Why is everyone ruining the theory that 1=2?

Another theory is that 3/3 doesn’t equal 1.

Proof:

1/3=0.3333333…

1/3*3=0.3333333…*3

3/3=0.9999999…

0.9999999… does not equal 1. So why do we say it does?

Ashwin

May 11. 2012

you cannot cancel 0 if it is on LHS and RHS…..

(a-b) and (a2 -ab) are equal to 0 in the above equations, hence they cannot be cancelled out……..

hence the above 5 proofs are utter nonsense………

Mark Respicio

Jan 27. 2013

What did you mean by subtitute? (Im just studying an elementary algebra) that why i dont know … ^_^