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24 votes
Given the function f(x) = (x + 2)/3 determine the slope of the inverse function of f(x) .

User Nitro
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1 Answer

13 votes
13 votes

First, find the inverse function of f(x). To do so, replace y=f(x) and isolate x from the equation:


\begin{gathered} f(x)=((x+2))/(3) \\ \Rightarrow y=((x+2))/(3) \\ \Rightarrow3y=x+2 \\ \Rightarrow3y-2=x \\ \therefore x=3y-2 \end{gathered}

Swap x and y to find the inverse function:


y=3x-2

Replace y=f¨-1(x):


f^(-1)(x)=3x-2

Notice that the inverse function is written in slope-intercept form, and the coefficient of the variable x is the slope. In this case, the coefficient of x is 3.

Therefore, the slope of the inverse function of f(x) is 3.

User Veda
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