Microsoft Excel creates spreadsheets, allowing for the simple visualization of data values. Graphing a particular mathematical function requires that the user generate the data values of the function. Fortunately, Excel also makes it easy to generate these values. After you have generated the outputs of the function, you can include any number of functions in a single graph. This can be useful to compare different functions.

Type an "X" in A1, the topleft cell, and a "Y" in the cell just to the right of that one, B1.

Type the starting value for "X" in cell A2, usually 0 or 1. Add 1 to this number and type it in cell A3.

Click and hold in cell A2 and drag to A3 to select both cells. Click and drag the small square in the lowerright of the selection, downwards. This will generate a number of X values for the graph.

Type the equation you want to chart in cell B2. Preface the equation with an "=" sign, and replace the "X" variable with "A2". For instance, if the equation was "f(x) = 3 + sin(x)" you would type "=3 + sin(A2)" in the cell.

Click B2 to select it. Click and drag the small square in the lowerright of the selection downwards until you reach the desired number of generated values.

Select all cells, starting from the topleft and ending at the bottomright.

Transform the selected cells into a chart. To do so, on the Insert tab in the Charts group, click "X Y (Scatter)" and "Smooth lines, no markers." If this option is not available at first, click the small arrow in the corner to open the Insert Chart dialog window, locate these options and select "OK."
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