Practice Problems
Work through our library of IB-style problems
Skills Checklist
Track your progress on all skills in this unit
Video Lessons
Watch comprehensive video explanations
Theoretical introduction to nCr, or (nr), and Pascal's triangle.
Using nCr to expand binomials like (1+2x)7.
Speed Run Quizzes
Test your speed and accuracy with timed quizzes
Practice Tests
Comprehensive exams with detailed feedback
