A geometric series is a+ar+ar2+…a + ar + ar^2 + \dotsa+ar+ar2+…
Prove that the sum of the first n n\,n terms of the series is
Sn=a(rn−1)r−1 S_n = \frac{a(r^n - 1)}{r - 1} Sn=r−1a(rn−1)200 exam-style questions on CCEA A Level Maths 3.3 Sequences and series (A-level only), covering 3.3.1 Sequences and series (A-level only), 3.3.2 Sequences and series (A-level only), 3.3.3 Sequences and series (A-level only), 3.3.4 Sequences and series (A-level only), 3.3.5 Sequences and series (A-level only), 3.3.6 Sequences and series (A-level only), 3.3.7 Sequences and series (A-level only), and 3.3.8 Sequences and series (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.