What is the difference between calculus and advanced functions?

I am almost down with advanced functions and I found it to be a little difficult. I've never been that strong in math so I expected this course to be hard for me. I tried pretty hard this year, and I think after the exam, I can maintain around a 85-87. I'm just wondering if calculus is a lot more difficult than functions to the people that have already taken both courses. I've heard multiple times that calculus can be easier, but I'm not quite sure.

Is it multiple choice i would really help