设 $\alpha_1=\left(\begin{array}{c}1 \\ 2 \\ -1\end{array}\right), \alpha_2=\left(\begin{array}{c}-1 \\ 3 \\ 1\end{array}\right), \alpha_3=\left(\begin{array}{c}4 \\ -1 \\ 0\end{array}\right)$, 利用施密特正交化过程将其化成规范正交向量组.
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