Question 486102
Functions are just operations that map some number or set of numbers to another number or set of numbers. They are usually denoted f(x) = ... (or some other letter besides f), so if you define a function f(x) = 2x + 1, then you can evaluate f(x) for a given x value, for example f(4) = 2(4) + 1 = 9. Or, if g(x) = 5x^2 + x, then g(1) = 5(1)^2 + 1 = 6.