The notation 'f(x)' looks intimidating, but it is one of the most powerful and useful ideas in all of math.

First, it is NOT f times x. It is pronounced 'f of x'.

'f' is simply the name of the function, like a name for a machine. We could also call it g(x) or h(x).

'x' is the input variable. It's what we are feeding into the machine.

'f(x)' as a whole represents the output. It is another name for 'y'.

So, the equation y = 3x + 2 can be written as f(x) = 3x + 2. They mean the exact same thing.

The power of this notation is that it's a command. If f(x) = 3x + 2, then 'f(5)' is a command to 'plug in 5 for x.'

f(5) = 3(5) + 2 = 15 + 2 = 17. So, when the input is 5, the output is 17.

This notation is incredibly efficient for showing what is being put into the function.

Don't fear it. See it for what it is: a beautiful and efficient way to describe the relationship between inputs and outputs.