Functions in the form of y = f(x) describe various sorts of line.
A line where for every +1 in x then y increases by x is quadratic.
A line where for every +1 in x then y doubles is exponential, y = 2 ^ x.
This can be inversed to create the logarithmic equivalents, for example:
For every doubling of x then y increases by 1, y = log2(x).
What is this called with quadratic equations?