, the domain
EL-9900 Graphing Calculator
Step & Key Operation | Display | Notes |
2 | Find the domain and the vertical |
| asymptote of f (x), tracing the |
| graph to find the hole at x = 1. |
Since f (x) can be written as x - 1
(x + 1)(x - 1)
consists of all real numbers x such that x ≠ 1 and x ≠ -1. There is no vertical asymptote where x = 1 since this value of x also makes the numera- tor zero. Next to the coordi- nates x = 0.9, y = 0.52, see that the calculator does not display a value for y at x = 1 since 1 is not in the domain of this rational function.
Find the x- and y-intercepts of f (x).
2nd F 
CALC 
6
Estimate the horizontal asymptote of f (x).
The y-intercept is at (0 ,1). No- tice that there are no x-inter- cepts for the graph of f (x).
The line y = 0 is very likely a horizontal asymptote of f (x).
The graphing feature of the EL-9900 can create the branches of a rational function separated by a vertical asymptote. The calculator allows the points of intersection to be obtained easily.
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