Using the Pivot and Gauss-Jordan Tool

• You can use the tab key to move from one cell to the next.
• This program has "clever tabbing": you can jump to the next row by tabbing twice at the end of a row -- experiment to see it work -- so there is no need to use the mouse to jump from one row to the next.
• The very top row contains labels for the columns; change them to anything you like.
• Decimal mode displays all the entries as decimals, rounded to the number of significant digits you have selected (up to 13, depending on your processor and browser).
• Fraction mode converts all decimals to fractions.
• Integer Mode eliminates decimals and fractions (using the method in Finite Mathematics and Finite Mathematics and Applied Calculus). It also automatically reduces each row to lowest terms if you use "Pivot" or "Row Reduce".
• "Save This" saves the current matrix and mode, and "Revert to Saved" restores the saved matrix.
• Row Operations To apply row operations to one or more rows, type them next to the row(s) as in the textbook. The format is as in the textbook, with the row you are changing written first. Here are some examples:
To do 4R2 - 2R1, type     4R2 - 2R1     next to Row 2
To do (1/8)R2 + R1, type     (1/8)R2 + R1     next to Row 2
Then press the "Do Row Ops" button once to do them. Press "Clear Row Ops" to erase all the row operations you typed in. (See the picture below for an example of some row operations.)
• Press "Undo" to undo any operation.
• "Row Reduce" reduces the matrix to "reduced row-echelon form."