Salam Academy
Paper 1 · Module

Series

4 subtopics≈ 165 min in total
  1. Binomial expansion

    How to expand (a+b)n(a+b)^n without multiplying out nn brackets, using Pascal's triangle or (nr)\binom{n}{r}, and how to pick out one term, such as the coefficient of x3x^3 or the term independent of xx.

    ≈ 45 min
  2. Arithmetic progressions

    Sequences that go up (or down) by the same amount each time: the nnth term, the sum of the first nn terms and why it works, and how to find unknowns from given terms or sums.

    ≈ 40 min
  3. Geometric progressions

    Sequences that multiply by the same number each time: the nnth term, the sum of the first nn terms and its proof, finding unknowns, and the growth and decay problems they model.

    ≈ 45 min
  4. Sum to infinity

    How adding infinitely many numbers can give a finite answer, the condition ∣r∣<1|r|<1 that makes it happen, and how to use S∞=a1−rS_\infty=\dfrac{a}{1-r} for recurring decimals, bouncing balls and exam problems.

    ≈ 35 min