A sequence u1,u2,u3,… u_1, u_2, u_3, \dots\,u1,u2,u3,… is defined by
u1=−1un+1=un2−1,n≥1 \begin{aligned}u_1 &= -1 \\u_{n+1} &= u_n^2 - 1, \quad n \geq 1\end{aligned} u1un+1=−1=un2−1,n≥1Find u2,u3 u_2, u_3\,u2,u3 and u4u_4u4.
Write down the value of u100u_{100}u100.
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.