Hello, I am a student of ENS Paris-Saclay in M2 at the Observatoire de Paris. I have already given in Paris courses in physics and maths second / first level as well as maths pre-eco level first year. I approach the subject freely and I adapt to the student, I draw the examples in my personal experience. I always prefer that the basics be understood before trying more in-depth exercises, I differentiate complex and difficult.