Matrix to the Power of T: Solving for AT in A=[2 4 6 8]

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Homework Statement


If A= [2 4 6 8] find AT


Homework Equations





The Attempt at a Solution


Would I simply distribute the T across the matrix like this: [2T 4T 6T 7T 8T]
 
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The superscript 'T' here indicates the transpose of the matrix A. For a matrix A, if the element in the ith row and jth column is ##A_{ij}##, then for the transpose matrix ##A^T##, the element in the ith row and jth column is ##A_{ji}##.

Note that if A is an mxn matrix, ##A^T## is an nxm matrix.
 
Daaniyaal said:

Homework Statement


If A= [2 4 6 8] find AT


Homework Equations





The Attempt at a Solution


Would I simply distribute the T across the matrix like this: [2T 4T 6T 7T 8T]

Ia A a true matrix? What you have written is a 4-dimensional row vector. Its transpose would be the 4-dimensional column vector with elements 2,4,5,8 in that order; that is:
[tex][2\;4\;6\;8]^T = \left[ \begin{array}{c}{2\\4\\6\\8}\end{array}\right].[/tex]
 
Ray Vickson said:
Ia A a true matrix? What you have written is a 4-dimensional row vector. Its transpose would be the 4-dimensional column vector with elements 2,4,5,8 in that order; that is:
[tex][2\;4\;6\;8]^T = \left[ \begin{array}{c}{2\\4\\6\\8}\end{array}\right].[/tex]

It is given to me by my teacher as a matrix, but I guess if it's a vector than it is a vector.

I did transpose it that way tho :D

Thanks!
 
Daaniyaal said:
It is given to me by my teacher as a matrix, but I guess if it's a vector than it is a vector.

I did transpose it that way tho :D

Thanks!

A vector is a special case of a matrix. However, perhaps you were supposed to interpret A as a 2x2 matrix, so A = [[2,4],[6,8]], where these are the two rows; that is:
[tex]A = \pmatrix{2&4\\6&8}.[/tex]
The transpose of A is
[tex]A^T = \pmatrix{2 & 6 \\4 & 8}.[/tex]

On the other hand, A to the power t is considerably more complicated. It would take several pages to write out the answer.