Linked Questions
32 questions linked to/from Looking for an intuitive explanation why the row rank is equal to the column rank for a matrix
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row rank= column rank, alternative proof [duplicate]
I am studying the theorem that states that the row rank of a matrix is the same as the column rank.
I understood the proof and managed to use it in specific examples using a matrix.
I am now, trying ...
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Intuitive proof of row rank = column rank? [duplicate]
Is it possible to give an intuitive/elementary proof of the theorem that says that the row rank of a (finite-dimensional) square matrix matrix equals its column rank?
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How come dim row A = rank if dim Im A is also = rank? [duplicate]
The following identities are true for a matrix $A$.
\begin{align}
\dim \mathrm{row}\, A &= \mathrm{rank}\,A \\
\dim \mathrm{Im}\, A &= \mathrm{rank}\, A \\
\dim \mathrm{row}\, A &= \dim \...
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Show that for any matrix $A_{m \times n}$ , the row rank and column rank are equal [duplicate]
Can somebody first please tell me what is the row rank and column rank of a matrix ? What is the relation of each with the rank of a matrix ? Any kind of explanatory proof would be very helpful , ...
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Calculate column rank of a matrix [duplicate]
How do I calculate the column rank of the matrix:
$$\begin{bmatrix} -2 & -4 & -6 & 0 \\ 0 & -12 & 24 & 0 \\ 0 & 0 & 28 & -4 \\ 0 & 0 & 0 & 0\end{bmatrix}...
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Which one result in mathematics has surprised you the most? [closed]
A large part of my fascination in mathematics is because of some very surprising results that I have seen there.
I remember one I found very hard to swallow when I first encountered it, was what is ...
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Geometric interpretation of $\det(A^T) = \det(A)$
$$\det(A^T) = \det(A)$$
Using the geometric definition of the determinant as the area spanned by the columns, could someone give a geometric interpretation of the property?
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Proof that determinant rank equals row/column rank
Let $A$ be a $m \times n$ matrix with entries from some field $F$. Define the determinant rank of $A$ to be the largest possible size of a nonzero minor, i.e. the size of the largest invertible square ...
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Why do elementary matrix operations not affect the row space of a given matrix?
I have shown that two of the three elementary operations will not change the image of the row space of the matrix: given a row vector $\vec{v}$, $k\vec{v}$ will span the same (scalar multiplication), ...
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Why do row operations not change the column rank?
From this question link, I got to know that row operation (row subtraction and row permutation) do change column space.
But still it seems that it does not change the column rank.
I am trying to prove ...
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Finding null space of matrix.
I need to make sure I'm understanding this correctly.
I skipped a few steps to reduce typing, but let me know if I need to clarify something.
Question asks:
Find $N(A)$ for $A$ = \begin{bmatrix}
...
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Complex conjugation does not change rank
I have a question about complex conjugation of a matrix. Prove that for any rectangular matrix $A$ the following holds
rank $A = \text{rank} \, A^*$ where $A^*$ is complex conjugate transpose of $A$.
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Rank of vectors
Prove that the rank of a system of vectors from $E^n$ does is not bigger than the dimension of the vectors.
For example the vectors $a,b,c$ are from $E^n$ so each of them has $n$ components (the ...
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$im(A)=im(AA^T)$ [duplicate]
If $A$ is an $n\times m$ matrix, is the formula $im(A)=im(AA^T)$ necessarily true? Explain.
I believe this to be true when $n=m$ but am unable to prove if it's true where $n\neq m$. I also don't ...
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Intuition: If the columns of a matrix are colinear, then its rows are also colinear.
For simplicity's sake, I'm working with a 3x3 square matrix in which none of the column or row vectors is the zero vector.
I tried graphing the columns of the matrix {{1,4,-3},{2,7,-5},{3,6,-3}} (...