Question

Write the first five terms of the sequences whose $n^{th}$ term is

$a_n=n(n+2)$

Answer 1

Here, $a_n=n(n+2)$

Putting n = 1, 2, 3, 4 and 5, we have ;

$a_1=1(1+2)=1\times 3=3$

$a_2=2(2+2)=2\times 4=8$

$a_3=3(3+2)=3\times 5=15$

$a_4=4(4+2)=4\times 6=24$

$a_5=5(5+2)=5\times 7=35$

Thus, the first five terms are ;

3, 8, 15, 24 and 35.