An arithmetic series is given by ∑n=15(bn+c)\sum_{n=1}^{5} (bn+c)∑n=15(bn+c) where b b\,b and c c\,c are constants. The sum of the series is 10.
Show that 3b+c=23b+c=23b+c=2.
Given the 5th term is 2 times the 2nd term, find the values of b b\,b and ccc.
326 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.