\[(x - 1,2)^{2} - 1,21 = 0\]
\[(x - 1,2)^{2} = 1,21\]
\[(x - 1,2)^{2} = {1,1}^{2}\]
\[x - 1,2 = 1,1\]
\[x = 2,3;\ \]
\[x - 1,2 = - 1,1\]
\[x = 0,1.\]
\[Ответ:0,1;\ \ 2,3.\]