Show matrix is invertible. THanks

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The discussion centers on proving the invertibility of a matrix defined by distinct real numbers x1, x2, ..., xn. The matrix is structured as a Vandermonde matrix, which is known to be invertible when the x values are distinct. Participants clarify that the matrix is indeed n x n, containing n rows and n columns, and emphasize the importance of the distinctness of the x values for the proof. The conversation highlights the necessity of confirming that no rows are lost in the matrix definition. Ultimately, the matrix A is confirmed to be invertible due to its Vandermonde structure.
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Homework Statement


Show matrix is invertible. THanks

The matrix A is de ned by
1 x1^2 x1^3 x1^4 ...x1^n-1
1 x2^2 x2^3 x2^4 ...x2^n-1
...
...
1 xn^2 xn^3 xn^4 ...xn^n-1

where x1; x2,... xn are distinct real numbers.

Homework Equations





The Attempt at a Solution


Homework Statement





Homework Equations


Show that A is invertible.


The Attempt at a Solution


Show that A is invertible.
 
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What have you tried?
 
No,invertible matrix should be a n×n matrix,you must have lost a row(x1,x2,x3,…xn)T,then it's a van de Monde matrix
 
panqihg said:
No,invertible matrix should be a n×n matrix,you must have lost a row(x1,x2,x3,…xn)T,then it's a van de Monde matrix
The matrix is n x n. There are n rows, each with n columns.
 
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