A sequence x1,x2,x3,… x_1, x_2, x_3, \dots\,x1,x2,x3,… is defined by
x1=2,x2=9xn=xn−1+xn−2,n≥3 \begin{aligned}x_1 &= 2, x_2 = 9 \\x_n &= x_{n-1} + x_{n-2}, \quad n \geq 3\end{aligned} x1xn=2,x2=9=xn−1+xn−2,n≥3Find x3,x4 x_3, x_4\,x3,x4 and x5x_5x5.
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.