Given data:
The given expression for the function is f(x)= 5/(x+3).
The expression for one-to-one function is,

The above expression shows that the given function is one-to-one.
The expressionn for the inverse function is,

Replace y by x in the above expression.

Thus, the given function is one-to-one and the expression for the inverse function is (5-3x)/x .