Write the first five terms of the sequences whose $n^{t h}$ term is $a_{n}=n(n+2)$
Write the first five terms of the sequences whose $n^{t h}$ term is $a_{n}=n(n+2)$
$a_{n}=n(n+2)$
Substituting $n=1,2,3,4$ and $5,$ we obtain
$a_{1}=1(1+2)=3$
$a_{2}=2(2+2)=8$
$a_{3}=3(3+2)=15$
$a_{4}=4(4+2)=24$
$a_{5}=5(5+2)=35$
Therefore, the required terms are $3,8,15,24$ and $35 .$
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