IMO Shortlist 1960 problem 2

For what values of the variable $x$ does the following inequality hold: $\dfrac{4x^2}{(1-\sqrt{2x+1})^2}<2x+9 \ ?$

Source: Međunarodna matematička olimpijada, shortlist 1960

rigoletto, May 4, 2012, 1:01 p.m.

EDIT (ikicic): nemojte pisati rjesenja ili hintove u komentare zadatka...

Last modified: arhiva, May 4, 2012, 3:32 p.m.

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