Question 1

Write the first five terms of the sequences whose nth term is a_n=n(n+2)

Answer

a_n = n(n+2)

Substituting n = 1, 2, 3, 4, and 5, we obtain

a₁ = 1(1+2) = 3

a₂ = 2(2+2) = 8

a₃ = 3(3+2) = 15

a₄ = 4(4+2) = 24

a₅ = 5(5+2) = 35

Therefore, the required terms are 3, 8, 15, 24, and 35.

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