Sum of n terms of an Arithmetic Progression Let a be the first term and d be the common difference of an A.P. is the last term where l = a + (n – 1) d. Sum of first n terms of the given A.P. is given by …(i) Writing in reverse order …(ii)…
nth Term of an Arithmetic Progression Let …….. be an A.P., with first term as a, and common difference as d. First term is = a (i) Second term = a + d (ii) = Third term = (iii) = [from (i)] = or = Fourth term or = [from (iii)] = …