MHB What Determines the Range of a Rational Function Like f(x) = 2/(x - 3)?

AI Thread Summary
The discussion focuses on determining the range of the rational function f(x) = 2/(x - 3). The range is defined as all the values the function can assume over its domain. Participants explore methods for finding the range, including graphing and analyzing the function's behavior near critical points, specifically the values 3 and 0. There is some confusion regarding the relationship between the domain of the inverse function and the range of the original function. Overall, the conversation emphasizes the importance of understanding the function's characteristics to accurately determine its range.
mathdad
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Find the range of
f(x) = 2/(x - 3).

1. What exactly are we looking for when we say RANGE of a rational function?

2. Is the domain of the inverse the range of the given function?

3. What is the easiest way to find the range? Graphing?
 
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1. All the values a function assumes over its domain.

2. Let's see:

y = 2/(x - 3)

x - 3 = 2/y

x = 2/y + 3

y^(-1) = 2/x + 3

What conclusions may we draw? (look at the values 3 and 0 in both functions).

3. Depends on the function (in my opinion).
 
greg1313 said:
1. All the values a function assumes over its domain.

2. Let's see:

y = 2/(x - 3)

x - 3 = 2/y

x = 2/y + 3

y^(-1) = 2/x + 3

What conclusions may we draw? (look at the values 3 and 0 in both functions).

3. Depends on the function (in my opinion).

I do not understand your answer to question 1.
I also do know what conclusions we can draw based on the values of 3 and 0 in both functions.
 
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