CAPE Pure Mathematics Unit 2 · May/June 2017 · Paper 1 · Question Q18

A sequence is defined as u_{n+1} = 1 - \frac{1}{1 + u_n}, where u_1 = 1 and n \in \mathbb{N}. The 20th term of the sequence is

1. (A)\frac{1}{20}
2. (B)\frac{1}{21}
3. (C)\frac{19}{20}
4. (D)\frac{20}{21}