Derivation is not difficult. As long as we understand the concept of derivative, there are many fewer problems. The rest is mathematical knowledge, such as tangents. Derivative is actually closely related to geometry. It is actually a good choice to understand with plane geometry.

I don't know if you have studied plane geometry. If you don't, it's hard. What we remember at that time was that senior one didn't learn about plane geometry. According to the actual situation. Only when you have a good foundation can you learn higher courses.