回復 13# jackyxul4 的帖子
信哥老師 我覺得應該有四個
隨著特徵向量固定後( EX:[3/5, 4/5)
可取的單範正交基底有兩個 (EX:[4/5, -3/5] OR [-4/5 , 3/5])
這樣取出來的U就有四個 對應的T也是四個。
①\( U=\Bigg[\; \matrix{\displaystyle \frac{1}{\sqrt{2}} & \frac{1}{\sqrt{2}} \cr \frac{1}{\sqrt{2}} & -\frac{1}{\sqrt{2}}} \Bigg]\; \),\(T=\Bigg[\; \matrix{2 & 7 \cr 0 & 1} \Bigg]\;\)
②\( U=\Bigg[\; \matrix{\displaystyle \frac{1}{\sqrt{2}} & -\frac{1}{\sqrt{2}} \cr \frac{1}{\sqrt{2}} & \frac{1}{\sqrt{2}}} \Bigg]\; \),\(T=\Bigg[\; \matrix{2 & -7 \cr 0 & 1} \Bigg]\;\)
③\( U=\Bigg[\; \matrix{\displaystyle \frac{3}{5} & \frac{4}{5} \cr \frac{4}{5} & -\frac{3}{5}} \Bigg]\; \),\(T=\Bigg[\; \matrix{1 & 7 \cr 0 & 2} \Bigg]\;\)
④\( U=\Bigg[\; \matrix{\displaystyle \frac{3}{5} & -\frac{4}{5} \cr \frac{4}{5} & \frac{3}{5}} \Bigg]\; \),\(T=\Bigg[\; \matrix{1 & -7 \cr 0 & -2} \Bigg]\;\)