Question 1201049
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<pre>

If your expression is  {{{sqrt(2x-4)}}},  then the necessary condition for the expression
to be defined over the real numbers is this inequality

    2x - 4 >= 0,


saying that the radicand is non-negative.


From this inequality, you have  

    2x >= 4  and further  x >= 2.


It is the <U>ANSWER</U>.
</pre>

Solved.