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36 votes
36 votes
Find the inverse of f(x) =3/x -10

User Eliana
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1 Answer

18 votes
18 votes

f^(-1)(x)\text{ = }(3)/(x+10)

Step-by-step explanation:

f(x) = 3/x -10

To get the inverse, let's make f(x) = y

y = 3/x -10

interchange y and x:

x = 3/y - 10

make y the subject of formula:


\begin{gathered} x\text{ =3/y - 10/1} \\ x\text{ = }\frac{3\text{ - 10y}}{y} \\ \text{cross multiply: } \\ xy\text{ = }3\text{ - 10y} \end{gathered}
\begin{gathered} xy\text{ + 10y = 3} \\ y(x\text{ + 10) = 3} \\ y\text{ = }(3)/(x+10) \\ f^(-1)(x)\text{ = }(3)/(x+10) \end{gathered}

User Otelia
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