Sequences
2 marks · EasyA sequence is defined by the nth term formula: . Find the first and fourth terms of the sequence.
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(a) 2
(b) 17
Common mistakes: Using n instead of n^2
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Marking points
M1 · 1 mark · Correct substitution for the first term: 1^2+1=2
A1 · 1 mark · Correct value for the fourth term: 4^2+1=17
Worked solution
For the 1st term: n = 1. 1^2 + 1 = 2. For the 4th term: n = 4. 4^2 + 1 = 16 + 1 = 17.