Question

find s10 for ap is 2,4,6....,...

Answer 1

To find n th term the formula is an=a+(n_1)d use it to find the n th term

Answer 2

Sn= n/2+[2a+(n-1)d]
here, a=2
and d= 4-2=2
so,
s10=
$s10 = 10 \div 2 \times |(2 \times 2) + (10 - 1)2 |$
$s10 = 5 \times |(4) \times (9 \times 2)|$
$s10 = 5 \times (4 + 18)$
$s10 = 5 \times 22$
$s10 = 110$