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Computer Science/Linear Algebra

10 Transpose of a matrix

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Transpose of a matrix


Let's define a transpose matrix.

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Transpose of a transpose matrix A is same with the matrix A!

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Determinant of transpose


Let's assume determinant of any nxn matrix B is equal to the determinant of B's transpose.

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Then will it be the same if the matrix is (n+1) x (n+1)?

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Transpose of sums and inverses


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)

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This means that C transpose is equal to the transpose of (A+B)!

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Rank(a) = rank(transposse of a)


The rank of matrix A is equal to the rank of its transpose.

The rank of A transpose is equal to the dimension of column space of A transpose. This is equal the number of basis vectors for the column space of A transpose.

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Same applies to A.

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Showing that A-transpose x A is invertible


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Let's study a transpose times A.

A transpose A will be a square matrix.

To show that is invertible, we have to prove all the columns are independent.

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And if you get a k by k identity matrix, it means that your matrix is invertible.

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This is the same thing with Av dot Av.

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So we know Av must be equal to zero.

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If v is a member of the nullspace of A transpose A & v is also a member of the nullspace of A, It only contains the zero vector!

This means that the only solution is the x is equal to the zero vector. That means that the column s of A tranpose A are linearly independent!!

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