Below you can see videos arranged according to the chapters in the textbook. There is another page with past papers here.

Buy the official course textbook, exam practice questions and revision guide here:

Textbook

Exam Practice

Revision Notes

Chapter 3 Applications of equations and inequalities in one variable
Chapter 4 Sequences and recurrence relationships
Chapter 10 Permutations and Combinations

Note: The syllabus for this paper changed in 2019 (see the official website for more details).  Previously I made a playlist of past paper questions by topic. You can view it below, but some of the topics are no longer in the syllabus.