Решите уравнение: x^4-7x^2+6=0.

\[x^{4} - 7x^{2} + 6 = 0;\ \ \ \ \]

\[\ \ t = x^{2};\ \ t \geq 0.\]

\[t^{2} - 7t + 6 = 0\]

\[D = ( - 7)^{2} - 4 \cdot 1 \cdot 6 =\]

\[= 49 - 24 = 25;\ \ \ \sqrt{D} = 5.\]

\[t_{1} = \frac{7 + 5}{2} = \frac{12}{2} = 6;\ \ \ \ \ \ \ \ \ \]

\[t_{2} = \frac{7 - 5}{2} = \frac{2}{2} = 1\]

\[Ответ:\ \pm \sqrt{6};\ \pm 1.\]