Question

Observation for n = 4 , Sn = _______, For n =12 , Sn = ______ ??
Plzz answer this no silly answer otherwise i report X(​

Answer 1

Step-by-step explanation:

for n= 4

sn= 2(2a+3d)

= 4a+6d

for n=12

sn=6(2a+11d)

=12a+66d