[" d first "n" terms of an A.P.is "m^(2):n^(2)" .Show that the "],[3C=7cm,AB=6cm" and "/_ABC=60^(@)" .Constr "]

The sum of first n terms of an A.P.is 5n-n^(2) . Find the nth term of this A.P.

If the sum of n terms of an A.P.is 2n^(2)+3n then write its nth term.

The sum of the first n terms of an A.P.is 4n^(2)+2n. Find the nth term of this A.P.

If n^(th) term of an A.P.is 2n+1. Find the sum of n term.

The sum of first n terms of an A.P. is S_n .If S_n=n^2p and S_m=m^2p(mnen) .Show that S_p=p^3 .

The sum of the first n terms of an A.P.is 3n+n^(2) find "(1)" the first term "(2)" and the sum of the first two terms

If the sum of n terms of an A.P.is S_(n)=3n^(2)+5n. Write its common difference.

The sum of first n terms of a certain series is given as 2n^(2)-3n . Show that the series is an A.P.

The sum of n terms of an A.P.is 3n^(2)-n. Find the first term and common difference of A.P.