Answer
$a_n=(n-1)(\pi)$
$a_{51}=50\pi$
Work Step by Step
RECALL:
The $n^{th}$ term of an arithmetic sequence can be found using the formula:
$a_n = a_1 + (n-1)d$
where $a_1$ = first term and $d$ = common difference
The given sequence has:
$a_1=0$;
$d=\pi$
Substitute these values into the formula for the $n^{th}$ term to obtain:
$a_n=a_1 + (n-1)d
\\a_n=0+(n-1)\pi
\\a_n=(n-1)(\pi)$
To find the 51st term, substitute $51$ for $n$ to obtain:
$a_{51} = (51-1)(\pi)
\\a_{51}=50(\pi)
\\a_{51}=50\pi$