The fifth term of the sequence for which t1 = 1, t2 = 2

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The fifth term of the sequence for which t₁ = 1, t₂ = 2 and t_{n + 2} = t_n + t_{n + 1}, is

1. 5
2. 10
3. 6
4. 8

Correct Option: D

From the question ,
t_{n + 2} = t_n + t_{n + 1}
Putting on n = 1 , 2 and 3 respectively , we get
t₃ = t₁ + t₂ = 3
t₄ = t₃ + t₂ = 3 + 2 = 5
∴ t₅ = t₄ + t₃ = 3 + 5 = 8