When you evaluate functions, it’s really important to avoid some common mistakes that can make things tricky. Here are some errors you should watch out for to help you succeed:

1. Not Substituting Correctly:
   Make sure to replace the variable with the right value all the way! For example, in the function ( f(x) = 3x + 2 ), if ( x = 4 ), you should do this:
   ( f(4) = 3(4) + 2 ).
   Don't just add ( 2 ) to ( 4 )!

2. Ignoring Order of Operations:
   Remember to follow the order of operations, also known as PEMDAS! This means:

   • Do any calculations in parentheses first.
   • Then work on exponents.
   • After that, do multiplication and division from left to right.
   • Finally, handle addition and subtraction.

3. Not Checking Your Work:
   Taking a moment to double-check can really help! After you find the answer for the function, plug that value back into the original equation. You can also use a calculator to make sure your answer is correct.

4. Missing Domain Restrictions:
   Some functions have certain values you can’t use (like dividing by zero). Always check these limits to avoid mistakes!

By avoiding these common errors, you can get really good at evaluating functions quickly! Keep practicing and enjoy learning math! 🎉