The purpose of this question is to show you the syntax needed to enter matrices in WeBWorK when there is only one answer box for entering a matrix (which is not obvious) or when there are multiple answer boxes for entering a matrix (which is obvious). The examples below should be self-explanatory, so you can jump to them if you want; however, a detailed explanation follows if you want to read more.

Matrices use square brackets to enclose items in lists. A matrix with one row, such as a row vector, is a comma separated list enclosed by square brackets. A matrix with more than one row or a column vector is a comma separated list of lists, where each list uses square brackets to enclose its items. Your answers must use square brackets to enclose each row in a matrix or in a column vector. Also, a pair of square brackets is needed to enclose a matrix with more than one row (e.g., a $2 \times 3$ matrix and a $2 \times 1$ column vector have multiple rows so they need extra square brackets, but a $1 \times 3$ row vector has only one row so it does not need extra square brackets). Your answers may have spaces and line breaks in them, such as

Enter the matrix $\left[\begin{array}{ccc} 1 &2 &3\cr 4 &5 &6 \end{array}\right]$ as [[1,2,3],[4,5,6]]


Enter the column vector $\left[\begin{array}{c} 1\cr 4 \end{array}\right]$ as [[1],[4]]


Enter the row vector $\left[\begin{array}{ccc} 1 &2 &3 \end{array}\right]$ as [1,2,3]


Entering a matrix using multiple answer blanks is straightforward -- just put each matrix entry into its own answer blank.
Enter the matrix $\left[\begin{array}{ccc} 1 &2 &3\cr 4 &5 &6 \end{array}\right]$ with one matrix entry per answer box.
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