grandes-ecoles 2010 QIIG3

grandes-ecoles · France · centrale-maths2__pc Matrices Diagonalizability and Similarity
Let $X, H, Y$ be three elements of $\mathcal { M } _ { 0 } ( 2 , \mathbb { K } )$ such that $(X, H, Y)$ forms an admissible triple (i.e., $[H,X]=2X$, $[X,Y]=H$, $[H,Y]=-2Y$).
Show using questions II.F and II.C that there exists a matrix $Q \in GL ( 2 , \mathbb { K } )$ satisfying $X = Q X _ { 0 } Q ^ { - 1 }$.
Let $X, H, Y$ be three elements of $\mathcal { M } _ { 0 } ( 2 , \mathbb { K } )$ such that $(X, H, Y)$ forms an admissible triple (i.e., $[H,X]=2X$, $[X,Y]=H$, $[H,Y]=-2Y$).

Show using questions II.F and II.C that there exists a matrix $Q \in GL ( 2 , \mathbb { K } )$ satisfying $X = Q X _ { 0 } Q ^ { - 1 }$.