Pseudo-proof 2 = 1

Watch closely: I will prove that \(2 = 1\).  Your job is to show why such a logical proof could possibly be wrong.  It isn’t sufficient to point out that the answer is ridiculous.

\[a = b\] \[a^2 = ab\] \[a^2 – b^2 = ab – b^2\] \[(a-b)(a+b)= b(a-b)\] \[a+b = b\] \[2b = 1b\] \[2=1\]


multiply both sides by a

subtract b2


cancel like factors

since a = b

divide by b