Find a non-zero vector in each space
Emily Wong
The problem is given below:
My result regarding to question 1 is given below(Calculated in maple):
Then, my question is how to solve the question 2? I'm in doubt what even to do. Could someone explain me, what to do?
$\endgroup$3 Answers
$\begingroup$The vectors that form a basis for the column space are certainly in the column space. You can choose one of these.
$\endgroup$ 2 $\begingroup$Hint:
For the column space, pick any (nonzero) column.
For the row space, pick any (nonzero) row.
For the null space, notice that first and third columns of $A$ are equal, which means that
$$A\begin{bmatrix} 1 \\ 0 \\ -1 \\ 0\end{bmatrix} = 0.$$
$\endgroup$ $\begingroup$Other than just applying formulas, do you understand the meanings of these words? To get a vector in the column space, take any one of the columns of the matrix. To get a vector in the row space take any one of the rows of the matrix. A vector in the null space is any vector, v, such that Av= 0. That's the only non-trivial part of (2).
$\endgroup$