Question

Ap is a,a+d.....a+(n-1)d find sn

Answer 1

Answer:

Step-by-step explanation:

first term=a

common difference=d

tn=a+(n-1)d

Sn = n/2(a+l)

=n/2(a+a+(n-1)d)

therefore ,Sn=n/2(2a+(n-1)d