\[\boxed{\text{879.\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]
\[x^{2} - 4x + 1 = ?\]
\[при\ x = \frac{1}{4}:\ \ \ \]
\[\left( \frac{1}{4} \right)^{2} - 4 \cdot \frac{1}{4} + 1 =\]
\[= \frac{1}{16} - 1 + 1 = \frac{1}{16};\]
\[при\ \ x = - 3:\ \ \ \ \ \]
\[( - 3)^{2} - 4 \cdot ( - 3) + 1 =\]
\[= 9 + 12 + 1 = 22;\]
\[при\ x = 2 - \sqrt{3}:\ \ \]
\[\left( 2 - \sqrt{3} \right)^{2} - 4\left( 2 - \sqrt{3} \right) + 1 =\]
\[= 4 - 4\sqrt{3} + 3 - 8 +\]
\[+ 4\sqrt{3} + 1 = 0.\]