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