\( \definecolor{colordef}{RGB}{249,49,84} \definecolor{colorprop}{RGB}{18,102,241} \)
Consider the following calculation program:
  1. Choose a number.
  2. Add 3 to the chosen number.
  3. Multiply the result by the original chosen number.
Let \(x\) be the number chosen initially. Determine the function \(f\) that corresponds to the result obtained with this program.
Choose one answer: