A ‘Proof’ that 2 = 1

The above image ‘proves’ that 2 is equal to 1. Can you determine the flaw in the reasoning that is presented?

Scroll down for a clue and further down for the answer.

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Clue: The 5^th line doesn’t follow from the 4^th line

Scroll down for the answer.

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Answer: The 5^th line doesn’t follow from the 4^th line. This ‘proof’ falls under the “division-by-zero fallacy”. Going from the 4^th line to the 5^th line involves a division by “a-b”. This cannot be achieved as we initially stated that a=b therefore a-b would be zero. Dividing by 0 makes an undefined answer thus the proof isn’t valid.