Question
Write the first five terms of the following sequences whose $n^{th}$ terms are:
$a_n=2 n^2-3 n+1$.
$a_n=2 n^2-3 n+1$.
✓
Answer
$a_n=2 n^2-3 n+1$
The given sequence is $a_n=2 n^2-3 n+1$.
To write first tive terms of given sequence an, we put $n=1,2,3,4,5$. Then we get
$ a_1=2.1^2-3.1+1=2-3+1=0 $
$ a_2=2.2^2-3.2+1=8-6+1=3 $
$ a_3=2.3^2-3.3+1=18-9+1=10 $
$ a_4=2.4^2-3.4+1=32-12+1=21 $
$ a_5=2.5^2-3.5+1=50-15+1=36$
$\therefore$ The required first five tms of given sequence $a_n=2 n^2-3 n+1$ are $0,3,10,21,36$.
The given sequence is $a_n=2 n^2-3 n+1$.
To write first tive terms of given sequence an, we put $n=1,2,3,4,5$. Then we get
$ a_1=2.1^2-3.1+1=2-3+1=0 $
$ a_2=2.2^2-3.2+1=8-6+1=3 $
$ a_3=2.3^2-3.3+1=18-9+1=10 $
$ a_4=2.4^2-3.4+1=32-12+1=21 $
$ a_5=2.5^2-3.5+1=50-15+1=36$
$\therefore$ The required first five tms of given sequence $a_n=2 n^2-3 n+1$ are $0,3,10,21,36$.
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