Question 1157919: I don't have a graphing calculator and I would like to know how to solve this in details please...
Analyze the graph of the function R(x)=(7)/(x^2-36). To graph R using a graphing utility, determine an appropriate viewing window necessary to obtain a complete graph. Choose the correct answer below.
A.
[-12,12,2] by [0,4,1]
B.
[-12,12,2] by [-4,4,1]
C.
[0,12,2] by [-4,4,1]
D.
[-12,12,2] by [-4,0,1]
Answer by greenestamps(13334) (Show Source):
You can put this solution on YOUR website!
Factor the denominator to show the function as

The graph will have vertical asymptotes at x=-6 and x=6; so the window must include both of those x values. That eliminates answer choice C.
The factors of (x+6) and (x-6) each occur only once. That means that from one side to the other of x=-6, and from one side to the other of x=6, the sign of the function will change; so the window must display both positive and negative function values. That eliminates answer choices A and D.
The only choice left is B.
Here is a graph using that window:

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