Function and Inverse, Graphs, Domain and Range, given the function x = 2x - 4
- Thread starter amnetta
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I am not sure this has been expressed correctly? What do you mean the function x=2x-4 ? do you mean f(x)=2x-4?
Can you post the question exactly as it has been given to you? Do you have a screenshot?
And what you already know and where you are stuck? We can help here but there is no point just doing the question for you, hope you understand?!
Can you post the question exactly as it has been given to you? Do you have a screenshot?
And what you already know and where you are stuck? We can help here but there is no point just doing the question for you, hope you understand?!
Dr.Peterson
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Presuming that you mean to say, "Given the function f(x) = 2x - 4", you want to find the inverse function [imath]f^{-1}[/imath]. Here is a source about inverse functions:
There are a couple somewhat different ways to find an inverse, so if what you see there seems different, please show us what you were taught, so we can try to use the same approach.
And here are our instructions for asking a question well:
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Steven G
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f(x) = 2x-4
In words, what does f do to the input x. Answer, it doubles the input and then subtracts 4.
Suppose you were using your calculator and after many computation you arrived at say 2005. Now by accident you multiplied that number by 2 and then subtracted 4. How would you retrieve the number 2005 (since you forgotten that it was 2005)?
You could start over again making all those calculations OR you could add back the 4 and then divide by 2. The function that adds 4 and divides by 2 IS the inverse function. What do you thing that f-1 equals?
In words, what does f do to the input x. Answer, it doubles the input and then subtracts 4.
Suppose you were using your calculator and after many computation you arrived at say 2005. Now by accident you multiplied that number by 2 and then subtracted 4. How would you retrieve the number 2005 (since you forgotten that it was 2005)?
You could start over again making all those calculations OR you could add back the 4 and then divide by 2. The function that adds 4 and divides by 2 IS the inverse function. What do you thing that f-1 equals?