Question

a, a+d,a+2d,....,l are n terms of an A. P. find (n-1) term of it in the term of l

Answer 1

L=a+(n-1)d ie a= L-(n-1)d
(n-1)th term = a+(n-2)d
                   = L-(n-1)d + (n-2)d
                   = L -dn +d +dn -2d
                   = L-d, final answer


Hope This Helps :)