In the first four activities, we learned about the Geometry tools in GeoGebra. Here, we learn how to plot graphs. In this tutorial, we graph the functions and  \( f(x) = e^x \) and then reflect the graph of f about the graph of \(y = x \). Try them yourself first and if you have difficulties, read the Construction Steps below.

Expected Output



Graphing Window

Construction steps

  1. To plot the graph of \( f(x) = e^x \), click on the Input bar (right of the + button on the left window) and type  f(x) = e^x , then press the ENTER key on your keyboard.
  2. Plot the graph of \( y=x\).
  3. Select the Point tool and click on the graph of f. This will plot point A.
  4. To plot point B with reverse coordinates as A, type  B = (y(A), x(A)) . The command y(A) returns the y coordinate of A and  x(A) returns the x coordinate of A.
  5. Right-click on B and then select Show Trace.
  6. Move point A and observe what happens.

Notes

  • To plot points, just type the name of the point and then the coordinates. For example, A = (2,3) for point A on (2,3).
  • GeoGebra supports both the y and f(x) notations.

Questions for Discussion

  1. How is the trace of point B related to the graph of f and the graph of \( y = x \)?
  2. What do you think is the equation of the trace of B?

Last modified: Friday, 26 January 2024, 4:43 PM