An arithmetic series is defined by its first term p p\,p and its common difference qqq.
Prove that the sum of the first n n\,n terms of this series is
12n[2p+(n−1)q] \frac{1}{2}n[2p + (n-1)q] 21n[2p+(n−1)q]178 exam-style questions on Edexcel A Level Maths Sequences and Series, covering 3.1 Arithmetic Sequences, 3.2 Arithmetic Series, 3.3 Geometric Sequences, 3.4 Geometric Series, 3.5 Sum to Infinity, 3.6 Sigma Notation, 3.7 Recurrence Relations, and 3.8 Modelling with Series. Each one has a worked solution and a mark scheme showing where the marks go.