Question

if sn =2n²+3n , then d =

Answer 1

Sum=
$\frac{(2a - d)n + d {n}^{2} }{2} = 2 {n}^{2} + 3n \\ \: comparing \: both \: sides \\ \frac{d}{2} = 2 \\ d = 4$

Answer 2

hope it helpss........ :)