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Is it possible to write x^2 on the blackboard?(ToT2007-Fall)

Source:

September 3, 2011
calculusintegration

Problem Statement

Initially, the number 11 and a non-integral number xx are written on a blackboard. In each step, we can choose two numbers on the blackboard, not necessarily different, and write their sum or their difference on the blackboard. We can also choose a non-zero number of the blackboard and write its reciprocal on the blackboard. Is it possible to write x2x^2 on the blackboard in a finite number of moves?