Math Functions Question
Eg. If f(7x + 5) = 14x + 10 for all real x, what is f(x)?
Sparknotes gives the following explanation:
To discover what f(x) is, look where f maps 7x + 5. Simply put, f doubles the input: f(7x + 5) = 2 (7x + 5). Therefore, f(x) = 2x for all x.
But what if it is a more complicated function? Is there a more reliable way of getting the answer?