You may want to look at the help module Graphing a function for this module.
The way that a function appears in graph is determined in part by the ranges of the x- and y-axes. For example, if you use the same range for both axes on the TI-92 the function y = x will appear as shown below.
This is not what you might expect. The line y = x should make a 45 degree (pi/2 radian) angle with the x-axis. The reason it appears to be less steep is that the TI-92 screen is wider than it is high and the same physical unit on the screen represents different units for the x-axis and for the y-axis. To avoid the resulting distortion the x-axis range should be 238/102 times the y-axis range as shown in the two screen below.
