How to Graph Derivatives on TI-Nspire
The study of calculus should include a focus on the four key mathematical representations: algebraic, geometric, numeric, and verbal. The TI-Nspire Graphs application stands ready to take care of the geometric representation of calculus concepts. The Calculator application takes care of the algebraic piece, the Lists & Spreadsheet application takes care of the numeric piece, and the Notes application can take care of the verbal piece.
To graph the function y = x4 – 8x2 + 5 and its derivative on the same screen, follow these steps:
If you haven’t already done so, open a new Graphs page.
Graph y = x4 – 8x2 + 5 using the first available function on the entry line.
Press [CTRL][G] to open the entry line, then press
to open the Math template, highlight the derivative template, and press [ENTER].
See the first screen. You may want to resize the window.
Type x for the first field of the derivative template, and press [TAB] to move to the second field.
Type f1(x) or press [VAR] to see a list of available variables, select f1 from the list, and press [X] to complete the expression f1(x). Press [ENTER] to graph the derivative.
Move the cursor to the graph of the derivative and press [CTRL][MENU]→Attributes. Change the line style to medium and dashed to provide some visual clarity between the two graphs.
See the second and third screens. If you are using TI-Nspire CX, you may want to skip this step since each graph is a different color.
Try changing f1(x). The graph of f1(x) and its derivative updates accordingly.