To find $f(3)$ for the function $f(x) = x^2$:

1. Substitute $x = 3$ into the function $f(x)$.
2. Calculate the value.

$f(3) = 3^2$ $f(3) = 9$

So, $f(3) = 9$.

Would you like more details or have any questions?

Here are 5 questions you might want to ask next:

1. How do you find the derivative of $f(x) = x^2$?
2. What is the integral of $f(x) = x^2$?
3. How do you find the vertex of the parabola $f(x) = x^2$?
4. What is the domain and range of $f(x) = x^2$?
5. Can you solve $f(x) = x^2$ for $x = 5$?

Tip: When substituting values into a function, ensure that you perform the correct arithmetic operations step-by-step to avoid mistakes.