Question

Find the sum of first 13 terms of an AP -6, 0,6,12

Answer 1

If this solution really helps you

Than plz Mark me as brainliest

Answer 2

First term,a: -6

Common difference,d: +6

Formula for sum of first n terms of an AP

$S_n = \frac{n}{2}(2a+(n-1)d)$

Sum of first 13 terms

$S_{13} = \frac{13}{2}[2*-6+(13-1)*6]$

$S_{13} = \frac{13}{2}[60]$

$S_{13} = 390$

ANS: 390