Standard notation and function notation are used in almost the exact same way. The y variable in standard notation and f(x) in function notation are basically the same thing. In standard notation, x and y are the input and output respectively, while in function notation, if x is the input, then f (x) is the output. The main difference comes from how we write specific inputs and outputs.
&Standard Notation: y=2x+5
&Function Notation: f(x)=2x+5
If we take the given example equations and want to find the output when x=3, we have to notate things as shown below.
&Standard Notation: Evaluate when x=3.
&Function Notation: f(3)=?
When we want to show the solution, we write the following.
&Standard Notation: y=11
&Function Notation: f(3)=11
If we assume that we didn't know the function or the value of x, when looking at the solution in standard notation, we can only see what the value for y is 11 at some given point. However, in function notation, whether we know the function or not, we know that the function gives an output of 11 when the input is 3.
