Find the sum on n term of the A.P.

Show that (a–b)², (a²+b²) and (a + b)² are in A.P.

Find the sum of the following arithmetic progressions:

(i)to 10 terms

(ii)to 12 terms

(iii)to 25 terms

(iv)to 12 terms

(v)to 22 terms

(vi)to n terms

(vii)to n terms

(viii)to 36 terms

Find the sum of n terms of an A.P. whose n^th term is given by

If the n sum of a certain number of terms starting from first term of an A.P. is is 116. Find the last term.