Vectors, Matrices, and Tables > Creating Arrays and Tables > To Define an Array
  
To Define an Array
1. In a worksheet, click where you want to place an array.
2. On the Matrices/Tables tab, in the Matrices and Tables group, click the Insert Matrix list to open it.
3. Select the number of array rows and columns.
4. Click each placeholder and type its value.
Alternatively, press Tab to move through the placeholders.
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You can resize the matrix by dragging the bottom or right border of the matrix.