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Question 5 OT IUIf f(x) = 9x - 8, which of the following is the inverse of f(x)?O A. (*) - X=8B. f-1(x)X+98O c. f'(x) = X 48O D. F-1(x) = X-98SUBMIT

User Twan
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1 Answer

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To determine the inverse of a function we can follow these steps:

1. Replace f(x) by "y".

2. Switch the places of "y" and "x" on the expression.

3. Isolate the "y" variable on the left side.

4. Replace "y" by f^-1(x).

Let's apply these steps to the given expression:


\begin{gathered} f(x)=9x-8 \\ y=9x-8 \end{gathered}

Now we can apply the second step:


x=9y-8

We can now follow the third step:


\begin{gathered} 9y=x+8 \\ y=(x+8)/(9) \end{gathered}

Now the final step:


f^(-1)(x)=(x+8)/(9)

The expression for the inverse is (x+8)/9.

User Poonam
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