Triangular Similar Matrix question

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Alupsaiu
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Hi,

Is every matrix similar to a triangular matrix? If it is, anyone have an idea how to prove it?
Thanks
 
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Alupsaiu said:
Hi,

Is every matrix similar to a triangular matrix? If it is, anyone have an idea how to prove it?
Thanks

The proof can be done by induction. (Idea): In the field of complex numbers any n x n matrix has at least an eigenvector v. Complete v to get a basis of C^n. With respect to this basis, the first column of A has only the first element (let's call it a) eventually non zero, so A is similar to a block-triangular matrix, with a being the first 1 x 1 block and a certain (n-1)x(n-1) matrix B being the second block. Apply the inductive hypotesis to B and you get the result.
 
Every matrix is similar to a diagonal matrix or to a "Jordan Normal Form" both of which are upper triangular.
 
schur triangle theorem and it can be unitary similar