M4ML Course 2, Week 2 Quiz Notation

So I’m fairly sure I’ve got the correct answer to question one on the quiz, though I keep getting “incorrect” when I submit for grading. I’m reluctant to post my answer here (let me know if it’s OK), but I’d really just like to be sure I’m understanding what the correct notation is for the grader, my sense is it could be useful moving forward.

Thanks!

Which quiz are you referring to? There are two quizzes in C2 W2.