Mathematics for IGCSE & O level - Sequences (Section 2 - No. 8)
What are the first three terms of a sequence defined by the formula \(a_n = n^2 + 1\)?
1, 2, 3
2, 5, 10
3, 5, 7
0, 3, 8
คำอธิบาย
When n=1, a_1 = 1^2 + 1 = 2. When n=2, a_2 = 2^2 + 1 = 5. When n=3, a_3 = 3^2 + 1 = 10