Question

Find the first three terms of the sequence below.
T, = n2 + 2n +9

Answer 1

12, 17, 21 is the answer to the question

Answer 2

12, 17, 24

Explanation:

To find the first 3 terms, substitute n = 1, 2, 3 into the rule, that is

T₁ = 1² + 2(1) + 9 = 1 + 2 + 9 = 12

T₂ = 2² + 2(2) + 9 = 4 + 4 + 9 = 17

T₃ = 3² + 2(3) + 9 = 9 + 6 + 9 = 24