[beginarrayl 2&11&2endarray]

常见问题解答

• 求该行列式的值 \(\left[\begin{array}{l} {2}&{1}\\{1}&{2}\end{array}\right]\)

  

  $$3$$

• 求逆矩阵 \(\left[\begin{array}{l} {2}&{1}\\{1}&{2}\end{array}\right]\)

  

  $$\left[\begin{array}{ll}\frac{2}{3}& -\frac{1}{3}\\ -\frac{1}{3}& \frac{2}{3}\end{array}\right]$$

• 求特征值 \(\left[\begin{array}{l} {2}&{1}\\{1}&{2}\end{array}\right]\)

  

  $${\lambda }_1=1,{\lambda }_2=3$$

• 求行梯形形式 \(\left[\begin{array}{l} {2}&{1}\\{1}&{2}\end{array}\right]\)

  

  $$\left[\begin{array}{ll}2& 1\\ 0& \frac{3}{2}\end{array}\right]$$

• 求简化的行梯形形式 \(\left[\begin{array}{l} {2}&{1}\\{1}&{2}\end{array}\right]\)

  

  $$\left[\begin{array}{ll}1& 0\\ 0& 1\end{array}\right]$$