It seems like your input is incomplete. Are you defining a function $f(x)$? For example, you might want to define something like:

$f(x) = -x$

or

$f(x) = -x^2 + 3$

Please clarify your input, and I’ll assist you further! 😊

Do you want to clarify this equation or explore related concepts? Here are 5 related questions you might consider:

1. How do we evaluate functions for specific values of $x$?
2. What are common transformations applied to functions, like $-f(x)$?
3. How do we determine the domain and range of a given function?
4. What is the derivative of a function such as $f(x) = -x^2 + 3$?
5. How do we solve equations involving functions like $f(x) = -x$?

Tip: When defining functions, include operations like addition, subtraction, multiplication, division, or powers to make them more specific.