The concentration of a specific catalyst, CnC_nCn mmol/L, in a chemical reactor is recorded every hour. The process is modeled by the recurrence relation
Cn+1=15−Cn,n≥1 C_{n+1} = 15 - C_n, \quad n \ge 1 Cn+1=15−Cn,n≥1where the initial concentration is C1=4.5C_1 = 4.5C1=4.5.
Find the value of (i) C2C_2C2 (ii) C85C_{85}C85
Determine the value of ∑n=1100(4Cn−5)\sum_{n=1}^{100} (4C_n - 5)∑n=1100(4Cn−5).
231 exam-style questions on WJEC A Level Maths 3.4 Sequences and Series (A-level only), covering 3.4.1 Sequences and Series (A-level only), 3.4.2 Sequences and Series (A-level only), 3.4.3 Sequences and Series (A-level only), 3.4.4 Sequences and Series (A-level only), 3.4.5 Sequences and Series (A-level only), 3.4.6 Sequences and Series (A-level only), and 3.4.7 Sequences and Series (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.